Are Vertical Gardens a Viable Option?

Vertical gardening is quite popular. In fact, it might be trendier than it should be. In the right situations, it has practical applications and is appealing. Unfortunately…….

Vertical gardening is quite popular. In fact, it might be trendier than it should be. In the right situations, it has practical applications and is appealing. Unfortunately, it can be problematic in the wrong circumstances, probably more than it is worth. To help you decide whether to go for this creative idea, here are some issues associated with vertical gardening.


Limited growing space

In general, vertical gardens do not offer a lot of growing space for roots. As such, a vertical planter lacks the ability to support large plants unless it’s a heavy-duty structure, which in turn would just rack up the costs.  As a result, small farmers are limited to growing smaller plant varieties or those that grow at a much slower rate.   Careful and expansive planning done before setting up any part of the garden itself is an absolute must, because it’s the only way to avoid unnecessary problems down the road, like overgrowth caused by potential neglect, undergrowth due to inadequate solar protection or just general technical issues with watering or A/C systems.

High initial cost

Setting up a vertical garden requires a lot of money.   For starters, the price of urban land is often greater than that of farmland.   If you’re lucky and have a yard or some space around your house, you can try with some sheds or something similar, to maximize usable space for your garden. This option will allow you to utilize both horizontal and vertical space and you may also have a room that will function as a greenhouse.   However, you wouldn’t be out of the woods yet, since you have to buy various equipment needed for watering and other utilities.   Assuming you have an urban block of land, powering up the farmscraper costs a significant amount of money.   Additionally, creating the controlled environment of a vertical farm racks up the sum of money needed upfront.   Although pre-constructed vertical planting systems are specially designed to ease installation, maintenance, and watering, most of them are available at a much higher price than traditional pots.   Vertical farming calls for a significant investment but naturally less if doing it on a small scale in your backyard.


The potential to be messy

Although vertical gardens can provide insulation and shade, they usually hold moisture against walls and promote rot.    Same as other planters, those installed over decks or windows will drip, dirtying or staining whatever is below.    However, there are ways to get around such problems.

  • Insert your plants through a wire mesh material.
  • Place the plants close together to keep the dirt from escaping.   Succulents offer the most suitable results.
  • Give the roots enough time to grow and take hold before you change the orientation of your planters.   It will also help to keep the soil in place.
  • Attach your vertical garden to concrete walls since this type is not susceptible to rot.
  • Install free-standing vertical gardens.

Water-borne pathogens can spread faster

Diseases that disperse in water are likely to proliferate at a higher rate in vertical gardens.   The natural flow of water might carry water-borne pathogens from the top of the garden to the bottom.   As such, if a disease occurs at the upper part of a vertical garden, it will most likely spread to every plant below.   On the ground, this type of disease spreads at a slower rate since it can only travel as far as the flow or splash of water.

Watering and drainage might be a challenge

If you plan to grow indoors, watering and drainage are important issues to consider.   Many growers choose succulents or drought-tolerant plants as a solution to this problem.   Using smaller containers is also advisable since they are a lot easier to move for watering.   The highest risk are gardens maintained indoors, as they requires constant maintenance and monitoring of drainage system.   For example, neglect or use of low quality piping can cause leaks and ruptures that will further damage the structure in which the garden is set up, in this case walls, flooring, furniture etc.

Succulent Wall Garden
Succulent Wall Garden
The Rocks - Sydney
The Rocks - Sydney

The potential to dry out quickly

Vertical gardens that receive a lot of sunlight are known to dry out quickly, as a result of which plants weaken or die.   You need to consider the type of material to use when building a vertical planter.   For example, when making a gutter garden for lettuces and herbs, you should use a white plastic gutter instead of a dark metal trough since such a garden will be exposed to the sun almost always.   A dark metal gutter will heat up a lot faster than a white plastic one since the latter will reflect light and heat.

Despite all this they can look magnificent

Article written by:  Michael Fulkerson from Iowa, USA. April 19th 2017


Like Bacteria and Fungi, there are good & bad Nematodes & ones of no importance. The good ones are free living ones that…….

Are also called Eel Worms.   They are part of the Roundworm family just like the ones in your garden but a lot smaller in size. 0.5 to 1.5 mm long.
The females can just be seen with the naked eye but males are too small to be seen without magnification.   Some scientists classify animal roundworms (eg Barber’s pole, Pimply Gut worms of sheep & cattle) as being Nematodes but most people only think of Nematodes as being plant problems.
Like Bacteria and Fungi, there are good & bad Nematodes & ones of no importance.   The good ones are free living ones that break down organic matter, kill other Nematodes or trap & kill some Fungi, Bacteria, Algae, Actinomycetes, Protozoa and other Nematodes.

The good Nematodes do not attack living plants and are sometimes used to control Chafers, Lucerne weevil, cucumber beetle, some grasshoppers, & earwigs.  There is some evidence that some good Nematodes will weaken cotton Boll weevil by forcing the weevil to emerge too early & starve.

Parasitic and non parasitic nematodes
Parasitic and non parasitic nematodes

Then there are the disease causing ones that most people think of when they think of Nematodes.

Bad Nematodes or parasitic Nematodes need a living plant to infest and thus reproduce. They attack the roots of some plants and a few do attack the above ground plant parts.

The Nematodes that most people know about are those that attack Tomato plants.   They pierce the roots of the plant which responds by forming a gall that restricts the movement of water & therefore nutrients.   This means that the plant is less productive from the time it is attacked, so produces less fruit.

Nematodes have a very limited ability to move within the soil but are readily moved when infested soil, roots, bulbs, machinery, shoes, water etc are transported from one place to another.   They survive either attached to plant roots or as cysts containing their eggs that then survive until they can emerge and infest some other host plant roots.

Parasitic Nematodes prefer light, sandy, well aerated soil so tend to be a serious problem in the better types of soil that most gardeners aim for.

Nematodes are hard to control – Yes I did say control, not eliminate, as any vacuum in nature is quickly filled with some other organism good or bad – so control is the object.

Control Methods

1.     Toxic Chemicals or fumigation – usually Methyl Bromide but this has been banned in Australia for a few years now & is only allowed to be used by qualified people within Commonwealth Quarantine.

2.     Crop Rotation – Do not plant the same plant (or the same family of plant) in the same space for at least 3 years (or more if you have the space). This is so the Nematodes die out

White Potato Cyst Nematodes
White Potato Cyst Nematodes

3.       Use plants that repel Nematodes such as – Asparagus, Dahlia, African & French Marigold (they have an effect for up to 3 years in the soil), annual Salvia, Calendulas, radishes, White & Black mustard, turnip, onions, corn, some cowpeas, and velvet beans.   The cover crop of Crotalaria discourages Nematodes also.

4.      Spray with Neem oil.   It contains active ingredients like azadirachtin, nimbin, picrin, and sialin.   It is said to affect the natural hormone balance of the worm and other bugs so they behave unnaturally and die.   However it is best to use as a spray as drenching the soil is apparently not good for tomatoes, cabbages and onions.   Mix 1 tsp of neem oil to 1 litre of water and add 1/2 tsp of liquid dish soap for extra punch and spray on leaf surfaces

5.      Solarise the soil. This is done by digging the soil and breaking up any clods (This is important as the clods will not get hot enough to give control to the Nematodes), smooth the soil surface & water it thoroughly. Cover the soil with a sheet of thin, clear plastic making sure the edges are firmly held down to trap the sun’s heat.  The plastic sheet is left in place for 5-6 weeks in Summer when temperatures of up to 55o C can be reached and for longer in the cooler months.

Nematodes are usually killed at 50o C.   The soil is ready to be used again as soon as the plastic sheeting is removed.

6.      Plant plants that are resistant to Nematodes such as Broccoli, Brussels sprouts, chives, cress, garlic, leek. Others that have some resistance include; Globe artichoke, Jerusalem artichoke, horseradish, parsnip, rhubarb, spinach, sweet potato & turnip.   Highly susceptible crops include Cucumber & tomatoes.

Solarisation of soil and plant matter
Solarisation of soil and plant matter

7.      Another control is the use Organic amendments eg. some saw-dusts, that as they decompose give of some volatile fatty acids & phenols that deter Nematodes.

Today’s Did You Know…?

Queensland Department of Agriculture (now called Department of Primary Industries) used to have a world authority on Nematodes – Dr. Bob Colbran.   He used to identify about 6 or 8 new Nematodes each year but has now sadly retired.

“…In 1976, Bob Colbran was awarded the Agricultural Science Medal by the Australian Institute of Agricultural Science for his services to agriculture.   He finished his career as Director of the Plant Pathology Branch of the Queensland Department of Primary Industries, retiring in 1986.   When asked in 2007 what aspects of his work gave him the most satisfaction, he replied without hesitation: ‘finding and describing new nematode species and developing nematode control measures that were useful to farmers’.

Excerpt from CSIRO history of plant and soil nematology in Australia and New Zealand

Dr. Bob Colbran
Dr. Bob Colbran

Companion Plants as Ground Cover

…..Inadvertently you may plant things together that work well or simply won’t thrive because of other plants they are grown near

Companion Plants as Ground Cover

This article started out with me asking Bob what would be a good ground cover around your plants that was perhaps also useful in the kitchen. This naturally brought up the topic of Companion plants. Those that are either

– Good to plant together OR
– Bad to plant next to each other

In nature, plants grow in what appears to be a random mixture of plants that is in fact the result of natural selection of plants that are good to live together in that particular area.   If they are not compatible then the odd one out will not survive.   This will naturally happen in your garden as well.   Inadvertently you may plant things together that work well or simply won’t thrive because of other plants they are grown near.


The traditional farming methods of growing in man-made straight lines is now being replaced in many instance with gardeners trying to mimic nature by designing gardens with a harmonious blend of plants that work well together either to help each other thrive, reduce pests infestations or even act a decoys to attract pests to keep them off other plants.

By growing a lot of different types of plants together you are using what small space you have to the best advantage for growing the maximum amount of produce in that space.   And if done with a little knowledge you also reduce your pest problems.
The inter-planting of specific herbs between other plants allows you to pick a few leaves off an herb while harvesting the main crop, or perhaps cutting flowers for decoration on the kitchen table, all from the one small plot.


One example of mixed planting could be to grow Tomatoes with some Basil & some annual plants like Cosmos for their flowers.   The Basil will reduce aphids, mosquitoes & whitefly from the Tomatoes while the Cosmos attract bees to help increase the fruit rate of the tomatoes.
What better combination for a great pasta dish with a little table decoration as well.   Cosmos also attracts aphids and is often used as a decoy plant to keep aphids off other plants.

Or marigolds are great to plant around tomatoes to reduce nematode damage.   And bergamot will enhance the growth of tomatoes while attracting bees to the area, which in turn will help pollinate corn plants if you plant them near the bergamot.


The actual mix of companion plants will be determined by
– time of year
– climate
– the produce plants used
– compatible herbs/flowering plants
– quantity of plants needed to make a difference
You need to make your own mixture based on local information, but be aware that many people do not notice any discernible difference as results can vary according to the many different factors that affect each combination of plants.

There are some incompatible plants that should NOT be grown together such as Basil and Rue, or garlic and onions near beans or peas.   Why you may ask?   No one really knows for sure why basil and Rue are incompatible together.   They just don’t thrive side by side.


Beans are said to enrich the soil by fixing nitrogen (it is actually the Rhizobia that fix the nitrogen) which in turn makes onion and garlic grow green because they love nitrogen.   But onions and garlic will not produce good bulbs with too much nitrogen even though they love nitrogen.

Yet another use of companion plants is to use them in a compost heap to aid the breakdown of the waste material.

Dandelions are a weed in the lawn but are great for your compost heap.   It is best to dig them up before they seed so they don’t propagate.   The dandelions are rich in iron, copper, potassium, sulphur & manganese which add to the value of the compost.   Many people these days consider dandelions a nutritional treat to add to a green smoothie or salad and are therefore not considered a weed.   But I know in my yard there are way too many to eat.


Another brilliant plant that makes a beautiful fill-in plant around your ornamental plants is Comfrey.   It’s great to eat, great in your garden and great for the compost heap as well.

The bottom line ….By covering ALL exposed soil in your garden you shade out the opportunity for most of the weeds to germinate because they can’t do it without sunlight.   If they do germinate they will be weak from being shaded and easy to pull out before they set seed.   Do some research to find out the best ground cover for your garden whether it be herbs or grasses.   Herbs for cooking, flowers for the table or grass for the compost heap.


I love clover because it’s easy to mow over, feeds the bees, doesn’t grow too tall, is great as green fodder for your garden soil or grazing animals, and is actually edible when boiled.

Plus it is beautiful to walk on or “roll over in the clover”.


Today’s Did You Know…?

Cherry Tomatoes are a different group of tomato varieties (no specific species is given as a lot of tomatoes grown are a hybrid mixture of varieties) Cherry Tomatoes are usually hybrids but within Var. cerasiforme.


There are two types of Tomatoes:

(A) Determinate (these produce flowers at the end of each shoot, so fruit all at once & are squat plants.

(B) Indeterminate (these set flowers & fruit and then keep growing (some even up to 3 m high if well supported)

Big tomatoes produce fruit 10 – 14 weeks after planting while cherry tomatoes will fruit 11-13 weeks later.

A common “disease” is blossom End Rot.   It is NOT a disease but a calcium deficiency so can be prevented by using a handful of lime per plant, 2 months before planting, so the plant has enough time to take up the calcium early to prevent the “disease”

Nutrient Deficiencies

Nutrients (also called elements or fertilisers) are either mobile OR not-mobile. Mobile Nutrients are ones

Nutrient Deficiencies

Nutrients (also called elements or fertilisers) are either mobile OR not-mobile

Mobile & Non mobile deficiencies.
Mobile & Non mobile deficiencies. Credit:

Mobile nutrients

Mobile Nutrients are ones that move through the plant (ie are mobile) making ALL the plant the same colour. A plant therefore that is Nitrogen (N) deficient will be uniformly LIGHT green.

Some nutrients that are mobile are:

  • Nitrogen (N)
  • Magnesium (Mg)
  • Potassium (k)
  • Chlorine (Cl)
  • Molybdenum (Mo)

Non- mobile nutrients

These nutrients do NOT move through the plant so show up the deficiency in the NEW leaves (ie the leaves produced AFTER the plant experiences the nutrient deficiency). A plant with Iron (Fe) deficiency will have pale NEW leaves (an extreme Iron deficiency will  have white new leaves due to lack of chlorophyll as Iron is needed to make chlorophyll) but the rest of the plant will still be dark green.

Some nutrients that are NOT mobile are:

  • Boron (B)
  • Calcium (Ca)
  • Iron (Fe)
  • Manganese (Mn)
  • Sulphur (S)

A plant may be deficient in one nutrient & when that deficiency is corrected then a second deficiency may show up. The second deficiency may display only slight symptoms so may just seem to not grow as well and not show typical deficiency symptoms. This is the reason why it is more practical to apply a “shot-gun” fertiliser that contains a bit of each of the usual micro nutrients that are likely to be deficient.

Credit Twitter@FarmerRaviVKV
Credit Twitter@FarmerRaviVKV

Just repeating what I have said before, a plant can take up any nutrient only in solution  & that nutrient needs to be in an AVAILABLE form. A great example of this is the soil found in the Toowoomba region.   The red soil is red because of the high Iron content, but an Iron deficiency still is common because the Iron is chemically locked up and NOT available to the plants.

A list of other nutrient problems that may occur:

  • Excess nutrients The nutrient may be in excess and therefore available in toxic amounts. This can be because too much of  the nutrient is available at one time. EG: If a fast release (soluble) fertiliser (like Urea) is used but left without being washed in so the next time it rains or the garden is watered a bit, then a lot of the fertilizer is available  in toxic amounts in the root zone & so causes fertiliser “burn”.This often occurs when a bit of the fertilizer is lodged where the leaf joins the stem, gets wet then releases too much nutrient which then draws out the cell sap (as the fertilizer has a higher chemical strength than the cell contents) & the part of the plant that is in contact with the excess fertilizer is killed.
  • Too high or too low pH & so the nutrient is there but NOT available to the plants.
  • Fungi or bacteria attack. Either of these will break down the plant’s outer protective layer & allow entry of either bacteria & or fungi. This may look like a nutrient deficiency.
  • Insects eating the plant. This will also open up the plant to looking like a nutrient deficiency.
Urea Burn
Urea Burn Credit:
  • What looks like a disease but is really a nutrient deficiency. A great example of this is in tomatoes with the “disease” called Blossom Rot. It is NOT actually a disease but a Calcium (Ca) deficiency. Once the fruit show these symptoms it is too late for that fruit but by adding Calcium to the soil the next fruit will usually be free of the problem.
  • Herbicide effect. This may be over the whole plant but may also be on only a few leaves if it is a contact-only herbicide. If the herbicide is quite weak then there may be only slight symptoms.
Fluoride Toxicity.  
Fluoride Toxicity. Credit::
  • Fluoride toxicity. This does not usually occur but may if excessive amounts of fluoride have been added to the town water supply (by human error)
  • Excessively high or low temperatures. The leaves can be burnt by excessively high or low temperatures or if a plant is exposed to these temperatures too quickly without being slowly exposed to them from being in a sheltered place such as under a dark shad-cloth.
  • Salinity. This may be from water that is too high in salt (Sodium Chloride) from irrigation water, salt spray or some fertiliser (eg Potassium Chloride)
  • Time of the year. Gardenia’s sometimes in Spring show Iron deficiency due to too low a temperature in the winter that does not allow the plant to take up enough Iron.
  • Water logging. When the soil is full of water there is not any oxygen in it so the plant’s roots cannot breathe & adsorb any nutrients.
  • Drought. With not enough water then the plants cannot take up any nutrients in solution.
  • Toxin in the medium. There may be too much tannin in the bark & or potting mix as it has not leached out before it was bagged.
  • Excessive wind. Windburn can look like a nutrient deficiency such as wind burn from being in a open truck while being moved and not covered.
  • Air pollution. From being next to an industrial site where toxic fumes are being emitted.
lack of water in squash
lack of water in squash

So if you are not sure what is causing your nutrient problem add an all rounder fertiliser to correct the problem as it can be difficult trying to establish exactly what the deficiency might be without expensive and most likely unnecessary soil testing. Or use your Compost making sure your ingredients in your Compost heap come from many different sources or it too may be lacking in a particular nutrient.

Today’s Did You Know…?

It is desirable to grow plants (including lawn) next to a house on heavy clay soil such as what you might find in the Darling Downs. The ground is usually kept moist because you are watering your garden all the time, so that the clay is kept expanded and does not crack any solid building material eg bricks or Besser blocks. Timber can move a little to accommodate any soil movement so is not as likely to crack. Turf would keep the soil under it moist, shaded from the direct sun & reduce any reflected heat. Green couch is a good grass to use as it does all the above plus is highly salt tolerant. It is good near the ocean as well with salt spray being carried on the wind. But if the clay dries out then you get cracks in your brick work or plaster.

Cracked brick wall
Cracked brick wall

Photo references:

Carbon – How valuable is it for your soil?

Back in July 2016 I posted an article on chemicals in horse manure and the damaging effects it had on that man’s garden. Literally that same week I had a customer come by to pick up some more Compots and she told me she had the exact same problem in her garden when she added horse manure. She managed to resolve the problem by adding Activated Carbon to the soil.

Carbon – How valuable is it for your soil?

Back in July 2016 I posted an article on chemicals in horse manure and the damaging effects it had on that man’s garden. Literally that same week I had a customer come by to pick up some more Compots and she told me she had the exact same problem in her garden when she added horse manure. She managed to resolve the problem by adding Activated Carbon to the soil.

So this sent me on a mission to find out about Carbon and Activated Carbon because I sell what I call ‘Old Forest Carbon’, which is essentially old forest tree bark that has been slowly composting away for hundreds of years beneath a river bed that was dug up for sand mining. I wanted to know if this Old Forest Carbon was of any value to your soil and how it differed from Activated Carbon.

So with Bob’s help and hours and hours of research on Carbon, Soil Organic Carbon (SOC), agricultural importance of carbon and soil fertility, this is what I came up with.

The Carbon Cycle

As we all know all soil has a mixture of nutrients as does the air above it, both of which are constantly changing. Carbon (C) being one of those nutrients is mainly tied up with Oxygen to form Carbon Dioxide (CO2) in the air, and exists in the ground as a component of Soil Organic Matter (SOM).

It is constantly being taken up by plants, processed and released back into the atmosphere and soil as the plant grows and dies.
The Carbon Cycle.

Soil Flora, (Bacteria and Fungi) which live in the ground, also use CO2 to make soil material, eg Fungi Mycelium. These are the fine white threads you see in a rich or composted soil that has a lot of Fungi growing in it. Eg. Mushrooms – the fruiting visible part of the Fungi Mycelium.

All living material has Carbon in the form of Carbohydrates (Carbon, Hydrogen & Oxygen – ie. Sugar, Starch or plant fibre).

When a plant or animal dies the breakdown Bacteria and Fungi attack it and reduce it to Organic Matter that we call Compost.

Compost is a rich source of AVAILABLE nutrients which includes Carbon and can therefore be used to increase the Carbon content of your soil which aids plant growth along with all the other necessary nutrients.

Layers of Compost

Most soils used for agriculture over a long period of time will be lacking in Carbon (˂ 1%). Destroyed by frequent cultivation, stubble burning, overgrazing and fallowing that destroys the soil’s structure.

Farming methods need to change in order to maintain carbon levels or measures need to be taken to increase the carbon level by adding a Carbon rich supplement.

This can be done with a product rich in Carbon or by making your own Compost. Plus(for farmers)following more recent farming practices of not tilling the soil, not burning the stubble, reducing grazing, crops rotation, and green manures and composting.

The same can be done in your garden on a smaller scale or by adding a Carbon supplements as well as Compost. But remember to make your Compost from a variety of sources or you are likely to end up lacking a nutrient in your Compost that you won’t know is lacking until you grow some plants.

Farmers also now try to sequester (capture) Carbon to improve their land and plant quality. And to reduce the problems associated with increased Carbon in the Atmosphere from the burning of fossil fuels that is creating much of the green house problems we have today from putting excess carbon into the atmosphere.

Charcoal consists of Carbon and the left over ash that remains after water and volatile gases have been removed from such things as animal and vegetable material.

It is made by slowly heating wood in the absence of oxygen. Charcoal sticks used in Art are simply Charcoal bound together with a binding agent.


Activated Charcoal on the other hand is Carbon material that has been put through a high pressure hot steam system to remove matter from within its structure thereby increasing its capacity to absorb new material and thus ‘activate’ it (ready to absorb matter).

When it absorbs water and nutrients it allows plant roots to access and use these nutrients for growth, but it is also used to absorb harmful chemicals and poisons, and is used in many other applications such as water filters and mask filters.

Biochar is a form of Activated Charcoal used to promote soil health due to its very porous nature as it retains both water & water–soluble nutrients (remember that plants can obtain nutrients ONLY in solution)

Biochar also:-

  • Reduces leaching of E. coli through sandy soils (Some forms of E.coli act as Organic Matter decomposers)
  • Improves soil quality
  • Reduces soil vaporisation of green house gasses. Eg reduces Nitrous oxide by up to 80% & wipes out Methane both of which are more potent as greenhouse gasses than Carbon Dioxide
  • Reduces nutrient leaching
  • e. Reduces soil acidity and need for extra nutrient supplements, but due to its high absorption capacity it can reduce efficiency of soil applied pesticides. But if you don’t use pesticides then it doesn’t matter.

So where does that leave the Old Forrest Carbon?  From my research it’s a slow release carbon supplement (much like Biochar) but formed naturally beneath the river bed.  And like charcoal can aid in soil fertility management of nutrients, water and organic matter retention but this Old Forest Carbon contains 27% Carbon.

Check out the Terra preta soils found in the Amazon that mostly were built from carbon. See below.

“The charcoal is very stable and remains in the soil for thousands of years, binding and retaining minerals and nutrients”

Today’s Did You Know…?


Amazonian people inadvertently produced amazing soil known today as Terra Preta whose black characteristic come from its weathered charcoal content, bone, and manure mixed in with the relatively infertile Amazonian soil.

The charcoal was produced by a slash-and-char method of agriculture rather than a slash-and-burn system that has in the past helped cause much of the degradation of soil on farming lands today.

“The processes responsible for the formation of terra preta soils are:

  • Incorporation of wood charcoal
  • Incorporation of organic matter and of nutrients
  • Role of micro-organisms and animals in the soil”

Why use a Garden Cover / Mulch?

Garden covers come in many and varied varieties of material creating a layer on the surface of a growing media.

Mostly they are organic but……

Why use a Garden Cover / Mulch?

Garden covers come in many and varied varieties of material creating a layer on the surface of a growing media.

Mostly they are organic but may also be mineral or synthetic depending on your needs.

Organic covers (mulch) are generally a slow release fertiliser that gives the plants a bit of nutrient bit by bit as it decomposes.

They have four main uses:

  • To reduce evaporation and maintain moisture in the soil
  • Alter the soil temperature
  • Reduce weeds &/or
  • Reduce the compacting effect of heavy rain or irrigation.

Mulch can be:

  • Organic matter that decomposes quickly eg. straw, hay, compost, leaves, animal manures, sea-weed, grass clippings, etc
  • Organic matter that decomposes slowly eg. pine bark, wood chips, peanut husks, rice hulls, sugarcane, shredded bamboo etc.

Garden Covers can be:

  • Mineral materials eg. pebbles, gravel, crushed bricks, etc.
  • Synthetic materials such as black plastic, weed mat and other impervious material.


You will know yourself how soil dries out when exposed to the air.

Evaporation is therefore reduced by shading the soil & reducing the movement of water lost from the soil to the atmosphere.

A 4 cm straw layer will reduce the evaporation by about 70% BUT a layer that is too thick (one more than 10 cm) will hold too much water reducing the amount of water that gets through to the soil beneath.

So your mulch will be wet but your soil won’t be unless you are watering it underneath the mulch layer with say – a drip line system.

Some mulch is great to reduce evaporation but can pack down & form a water repellent layer (like paper and grass clippings). Making holes in the layers to water through, gives weeds an opportunity to take hold and grow.

This can be overcome by applying only a very thin layer of the product or mix it with some course material to keep it open.

Again the problem can be overcome by using a drip line water system beneath the mulch keeping the compacted layers on the top reducing the evaporation while watering the soil beneath.


Mulch also slows down the movement of water ACROSS the soil, while still letting water enter the soil rather than causing erosion of the topsoil layer. Again this depends on what you are using.

Black plastic film will reduce evaporation but also reduce any water & air going down into the soil & hence to the plant roots.

Temperature control

Mulch keeps the soil cooler in summer & warmer in winter allowing plants to grow for a longer period throughout summer & winter.

Organic mulches are great to use for summer as fine feeding roots of plants will grow up into the mulch. The top few centimetres are where a lot of the available nutrients are accessible to the plant roots (remember that plant roots can only take up nutrients in solution).


Back plastic needs to be covered with mulch to stop it from getting too hot and killing your plants. It can however be a great way to sterilise your garden bed of all bacteria and microbes.

Just let it sit uncovered for 2-3 weeks exposed to the sun and the heat generated under the plastic will kill the bugs. Then of course you need to re-fertilise your soil as it has killed everything- even the good bugs.

Reduce weeds

Many weed seeds will not germinate under a mulch layer as they use up all, or most of the food in their seeds, as they try to push through the mulch to reach the sunlight. Those that do emerge will be weak and easy to pull out.

Mulches with a lot of weed seeds in them should not be used (as a general rule) as that will only increase the weed seed supply

(note from Vicki – in my experience using grass clippings full of weed seeds and reapplying them each time you mow, tends to smother any new seeds trying to grow up. I personally have not yet found it to be a problem to date. However, I also get very little time to water so perhaps it is the lack of water rather than smothering each layer that prevents the seeds from germinating. It has also been said by someone, that tossing corn meal over your grass clippings will prevent seeds from germinating. But do not do this in your veggie garden or you may not get anything re-sprouting. I will be doing a test on this – coming soon- but if anyone has tried it we would love to get your feedback)

Nut grass will pierce through almost all mulches including plastic sheeting so needs to be killed BEFORE mulch is applied. (Bush Turkeys are great at removing nut grass – so Vicki says)

Vigorous grasses (eg green couch & Kikuyu), from an adjoining lawn area, need to be controlled before installing any mulch as they tend to climb over the top of any mulch and send underground runners into the muched area.


Paper, as mentioned above, either reduces evaporation, prevents water from entering the soil, or provides spaces for weeds to enter the soil and sprout. (Note from Vicki – I have found it to work really well if you soak your shredded paper for a period of time, spread it around your garden and then cover it with mulch. You will find the worms will come up to eat it and it turns into beautiful soil. But it does take time and needs to be kept moist. And just be sure to leave holes in the layer so water reaches the soil)

Of course never use plants that have recently been sprayed with herbicides eg. grass clippings recently sprayed with weed killer.

Reduce surface compaction.

Mulch reduces the force of raindrops or irrigation landing on the soil, therefore reducing the compacting effect.

Surface compaction reduces water and air movement down into the soil (& so to the plant roots) plus it reduces the dispersal of Carbon Dioxide from leaving the soil.


When an organic mulch is used that is still a bit fresh, you may need to added Nitrogen (such as Urea, Sulphate of Ammonia – about 5g N/m2). This is because the increase of nitrogen in the soil gets the nitrogen eating Bacteria working in overdrive eating up all the available nitrogen and depriving the plant of nitrogen. It is very short lived but the plant suffers as a result.

(note from Vicki – I have noticed in my experiments in the perspex pots that worms will take organic matter from the top layers deep down into the soil reducing the compaction, aerating the soil, and allowing for better drainage. This was especially evident when I used shredded bamboo as it decomposes very slowly. It does not do the same thing with grass clippings as grass clippings break down quicker to become composted soil.)


The ideal mulch thickness is:-

  • Fine compost & fine bark: 2-3 cm
    Coarse compost & coarse bark: 3-4 cm
    Chipped tree trimmings: 4-6 cm
    Bark nuggets, chopped sticks: 6-8 cm
  • Before applying any mulch, the soil needs to be thoroughly wet so the moisture is trapped under the mulch as mulch will often take up any water applied to it before it gets through to the soil.
  • A water drip feeder under the mulch is a good way to keep the moisture in the soil and reduce evaporation with your mulch layer on top.
  • Mulches can also be used to keep fruit off the soil (eg strawberries, cucumbers) so they are less affected by soil diseases.
  • Using compostable mulch is best because you can always mix it into the soil to break down into better soil and then add more on top. You can’t do this with mineral or synthetic coverings.

Today’s Did You Know…?


Using vinegar in your garden and outdoor living area :

  • Clean scissors of sticky material or grime by wiping the blade with a cloth dipped in full strength vinegar. Great for your garden shears.
  • Kill bad smells from the Compost bucket you keep on your kitchen bench – add some bi-carb soda as well to give it a good clean out.
  • Wipe away mildew by using full strength vinegar for heavy mildew & half strength for light mildew on your outdoor garden furniture.
  • Get rid of smoke odour from a bush fire (or burnt steak or oven) by placing a shallow bowl about ¾ full in the worst area or room. Fresh cigarette smoke is also “killed” by waving a cloth moistened with vinegar.
  • Unclog & deodorise your roof down pipes or blocked garden run off drains by using ½ cup of Bicarbonate of Soda followed by 1 cup of vinegar then flush with hot water when the foaming stops.
  • Clean any outdoor chrome & stainless steel fixtures using a light misting of full strength vinegar then buffing with a soft cloth. Great for the Bar-b-q.
  • Clean your silver jewellery after gardening (if you have forgotten to remove them) by soaking them in 1/2 a cup of white vinegar plus 2 tablespoons of Bicarbonate of Soda for 2-3 hours, rinse & dry with a soft cloth.
  • If you own any of those lovely old fashioned brass planter pots, you can clean and polish them by rubbing them with a paste of equal parts vinegar & salt OR 50/50 vinegar & Bicarbonate of Soda. Rinse & polish with a soft cloth.
Mixing Bi-Carb Soda with Vinegar
Mixing Bi-Carb Soda with Vinegar

NB. Do not use vinegar on pearls or gemstones as it will damage them.

Fire Ants are Our Problem Too

Fire ants (Solenopsis invicta) are quite small (2-6 mm) as is shown by the life size photo with one identifying feature being that they have …..

Fire Ants are Our Problem Too


Fire ants (Solenopsis invicta) are quite small (2-6 mm) as is shown by the life size photo with one identifying feature being that they have a range of sizes within each nest.

Their head and body is coppery-brown with a darker abdomen. They are very aggressive especially near their nest and will attack ‘anything’ that touches their nest, be it an animal, human or even a fallen branch.

Fire ants are natives of South America & entered southern United States in the 1930’s probably in soil as ships ballast.

It is now out of control with up to one third of the USA infested and little chance of ever eradicating the problem as it has become too widespread to eradicate.

Not only that it prevents people from using their backyard, sports ground, garden, small crop farm, etc and would be devastating if Australia were to become affected in the same manner.

As of July 1 2016, under the Biosecurity Act 2014, Fire ants are a category 1 restricted pest & you are required by law to notify Biosecurity Queensland if you think you see them anywhere or find them in your backyard.

In NSW it is the Department of Primary Industries & in Victoria it is the Department of Environment, Land, Water & Planning.

Picture showing original location of fire ants in South America

If possible, you should not try to eradicate them yourself, as this may inadvertently lead to spreading them further.Better to call in the experts.

To see if you are within a Queensland Biosecurity Zone go to:- There are 3 Fire ant Biosecurity zones in Queensland.

Genetic analysis has shown there have been 6 different attacks by Fire ants in Queensland. The first discovery was in 2001 when a gardener at the Port of Brisbane was stung, became unconscious and was taken to hospital. An Entomologist then discovered that this was the first KNOWN Fire ant colony.

Additional colonies were also found in Yarwin, Central Queensland, in 2006 & 2013. The 2006 colonies have been eradicated with the 2nd one expected to also be eradicated by July 2016.

Another colony was found at the Brisbane Airport in 2015.

The initial infestation spread to Ipswich, Logan, Redlands, the Scenic Rim, Gold Coast & the Lockyer Valley (A major Salad bowl area), with a colony also found in Port Botany, NSW in 2014.

It is thought that Fire ants were unknowingly imported into Brisbane up to 20 years ago.

By James Wetterer – Sociobiology, CC BY 3.0,


Most Fire ant nests do NOT have any obvious nest, often being just a bit of soil built up around a tuft of grass, so are easily missed and transported to new places (eg at a Flea markets or Fetes) in topsoil, mulches or potting mix.

It is for this reason that you must check which zone you are in before you ever move soil or mulch or anything from your garden to another garden or area.

Check the map link to find out if you are in a fire ant zone.

Fire ants are spread naturally during mating flights where the mated Queen can fly up to 2 km before finding a suitable nesting site.

They can significantly affect the Agricultural industry by attacking newborn or hatching animals, either killing them or damaging them enough to make them so weak they are less able to get around to collect food. Hence they feed excessively in a smaller area depleting the food source which leads to starvation.

Crop farm infestations make it well nigh impossible to farm an area due to the chance of being stung by a fire ant if you disturb their nest. This leads to loss of viable farming country and loss of income.

Picture of queen and workers during a nuptial fight
By I, Lamiot, CC BY 2.5,


Additionally, Fire ants can prevent animals reaching water without the animals being stung at all. They are aggressive feeders on small ground fauna including insects, spiders, lizards, frogs, birds, & mammals, so they quickly displace or eliminate some of our unique native ground fauna.

This has been shown to occur in Brisbane when detailed observations were made comparing fire ant infested areas versus clean areas with the same range of species.

If a person (or animal) disturbs a Fire ant nest, a LOT of workers swarm out of the nest and attack the object. There are often 100s of workers attacking at one time, each usually stinging up to 6 times. ie 200 ants stinging 6 times means 1200 stings are inflicted within a few minutes on the unsuspecting object.

The sting causes a painful, burning, itching sensation which tends to last for at least an hour. Multiple stings give the sensation that the body is on fire.

After a few hours or even a day or two, small blisters form at the sting sites.

Theses often become itchy, taking up to 10 days to heal with a high risk of secondary infection if the blisters or pustules break.

There is no other known toxin quite like that of a fire ant in Australia, so if you happen to be allergic to them you will get a violent reaction to the stings, and you won’t know this until you have actually been bitten.

In USA up to 200 people have died from a severe allergic reaction to Fire ant venom.


Today’s Did You Know…?


Some people try to kill the Fire ant nests by tipping petrol, or kerosene, into it and setting it alight.

This is NOT a good idea as only the top part of the nest is destroyed with all the worker ants within it.

BUT the Queen ant may be hidden further below than where the petrol reaches and is not killed so her worker’s either take her to a new site (which the Fire ant control people then do not know where it is) or look after her until she produces more eggs that then develop into workers.

In Australia (which leads the world in Fire ant eradication) the nest site is spread with a food that is mixed with a slow acting ant poison.

The object is to kill, or sterilise the Queen so she doesn’t produce more Worker ants to take over from the Worker ants that die.

A Worker ant has a life of only 6 weeks. This means that as the colony dies there are no Worker ants to look after the Queen and no more Worker ants to forage for food, or protect the Queen & the nest.


Remember to call in the experts if you find a Fire ant nest anywhere so you can be sure you don’t spread them.

A video on fire ants in Queensland

Searching the fire ants nests from the air


My favourite – a fascinating look at fire ants devouring a part of a worm with an interesting commentary on fire ant behaviour.


Rock Minerals

Rock minerals are not just crushed rock as most people think but are really a carefully blended mix of minerals such as Basalt, Gypsum, Lignite & Rock Phosphate.
There can be up to 100

Rock Minerals

Rock minerals are not just crushed rock as most people think but are really a carefully blended mix of minerals such as Basalt, Gypsum, Lignite & Rock Phosphate.

There can be up to 100 different minerals present but most are as very small amounts of trace elements and their use will create a reserve of these trace elements.


The common minerals supplied by Rock Minerals are Potassium, Calcium, & Magnesium but this depends on the natural mix of the rocks that they are derived from & mixed with to form the commercial product.

They may be in small amounts but trace elements need to be in small amounts otherwise they become toxic to plants even though they are essential to plant (& human) health.


Some trace elements are:

  • Manganese (Mn) It helps in the formation of chlorophyll
  • Iron (Fe) Important in forming chlorophyll
  • Boron (B) influential in the absorption of calcium
  • Molybdenum (Mo) Important in Nitrogen Fixation (especially in Legumes)

When plants are grown in a garden they use up the available nutrients which then need to be replaced – hence some form of fertilisers are used.

Some fertilisers are fast acting (eg most chemical fertilizers) while others are slow acting, usually as they are largely insoluble as are Rock minerals.

Unless the garden plant receives the nutrients in the correct amounts and at the time they are needed (eg. germinating or flowering or fruiting) they will not grow at their desired maximum rate.


A plant that is deficient in any one nutrient will not grow or fruit up to its potential & their fruit will also be lower in the element and therefore not be as nutritious to the person eating it.


The mix of natural mineral rocks are ground up into very fine dust & then often compressed into prills (small balls of compressed material) to make them easier to scatter.

When wet they dissolve into fine dust again. The smaller each particle of Rock mineral then the LARGER is its surface area. ie the LARGER the area per cubic yard for the soil fungi & insects, water, sun, etc to act on it and break it down & release the nutrients.

The speed of break-down is all relative compared to a soluble chemical fertiliser so natural Rock minerals are in effect Slow Release Fertilisers that have parts that may not completely break down & release their nutrients for up to one year.

This is why they are NATURAL fertilizers so are applicable to organic plant growing & so are safe to use on Australian Natives (some of which are sensitive to Phosphorus as they have an extra root system to take up all the available Phosphorus from the soil)


Rock minerals are usually applied at the rate of a generous handful per square metre both at planting & again in Autumn & Spring as a side dressing.

Due to them being almost insoluble, they are not leached out of the soil so are excellent for sandy soils.

Where you only have one time to apply rock minerals eg into the planting hole of a big plant (ie a citrus tree) then more would be used than if only top dressing the garden.

When Rock minerals are added to worm farms or compost, the added nutrients are also added to the garden plants with the worm casts or compost.

Today’s Did You Know…?

You can use Bicarbonate of Soda (also known as Sodium bicarbonate) to:-

  • Get rid of fish smells by soaking the raw fish in 1 litre of water with 2 tablespoons of Bicarbonate of soda for 1 hour.
  • Clean off garlic or fish smells from your hands using 2 teaspoons of bicarbonate of soda instead of soap.
  • Fluff up an omelette using ½ teaspoon of Bicarbonate of soda per 3 eggs used.
  • Clear a blocked drain with 1 cup of Bicarbonate of soda followed by 1 cup of hot vinegar (I’m sure you all know this one)
  • Use as a fire extinguisher for stove or car fires using a few handfuls of bicarbonate of soda even on electrical fires as it is dry

Horse Manure-be careful you don’t get more than you bargain for

I was going to condense this article for you all but have not had time, and I think the full article will be better for you all to read. It will certainly make you question where you get your horse poo from and what the horses were fed. A very eye opening read. ENJOY

Horse Manure-be careful you don’t get more than you bargain for

This is a great article taken from:-Town and Country Farmer. Jan/Feb 2016, Vol 33 No 1.
Article Written by Wayne Jeffery

I was going to condense this article for you all but have not had time, and I think the full article will be better for you all to read. It will certainly make you question where you get your horse poo from and what the horses were fed. A very eye opening read. ENJOY

Ever since Ian and I struck the first blow in our veggie patch adventure one of our main objectives has been to improve the soil quality. Almost every crop seems to thrive in nutrient rich, friable, well drained soil and when you start with a dry, rocky, dusty paddock you know it’s going to be a long haul.

Over the years we have worked hard on mulch collection and manure additions, especially in our poly tunnel glasshouse. This year we were particularly excited at the possibility of having home grown tomatoes as early as November. So can you imagine the sheer shock, frustration and anger that we felt on finding out that we have been inadvertently poisoning the very plants we are trying to nurture? Seriously! It turns out that the horse manure we have been collecting and mulching is laced with residual herbicides.

Now my gardening love affair with poo started way back on the family farm when dad and I used to clean out the neighbours chook sheds. We would shovel out the manure onto the trailer and then spread it around our apple trees. Dry, dusty, dirty work but great for the trees and at the right price!


Over the years the availability of chook poo has declined but around our area more and more properties seem to have bags of horse poo out. the front for sale. Ian and I arranged to leave a trailer at a nearby property and have it loaded with the mixture of rice hulls and horse manure when the stables were cleaned out. After a year of composting, how good would this stuff be for our soil? Tragically, we had never heard of Picloram or the Pyridne family of herbicides.

We had never heard of Clopyralid or Aminopyralid either. Nor nearly two hundred brand names of broad leaf herbicides.
Herbicides that can legally be used in hay and oat production. Herbicides that can end up in horse poo at levels lethal to a vast array of vegetables and flowering plants. Honestly, I can still barely believe it.

I was really keen to get our glasshouse tomatoes growing early this year. I purchased some advanced plants and planted them in beds freshly dug over with a healthy addition from our compost piles. Hard work but well worth it, or so I thought.

Growth was almost non existent. “Told you it was too early”, grumbled Ian. Gradually there was some growth but the plants became spindly with the leaves cupping and the tips curling. “Perhaps the rice hulls have leached all the nitrogen out”, mused Ian. “I knew we should have done a soil test”. Sadly, I knew it wasn’t just Ian being Captain Negator either. We also had plenty of other plants that weren’t flourishing.

As fate would have it I’d planted quite a decent patch of potatoes and filled the trenches primarily with our mulch. Rich, friable, well draining… Poison! The obviously mutated, twisted, fernlike growth of the potato leaves was the final pointer to our problem. So with that evidence and a lengthy stint giving google a solid workout the scope and impact of this residual herbicide problem has now become apparent.

If you search the internet yourself (clopyralid horse poo will give you a solid starting point) you will find accounts of the problem from numerous American states, the UK and here in Australia. Instances dating back ten years or more but still occurring today. For those of us who love our gardens there are many cases that make for sombre reading. Commercial composters selling tainted compost, small farmers losing their livelihood. I’m still wavering somewhere between outrage and depression at the situation.

I’ve added our compost to so many beds in the open paddock, no wonder the climbing beans are deformed and the peas were a waste of time.




These herbicides can still have an effect on certain plants at levels as low as one part per billion! Tomatoes and potatoes are particularly susceptible but the list also includes sunflowers, carrots, eggplants, peppers and many more.

Apparently most chemicals break down quickly in the composting process. Unfortunately Picloram, Clopyralid and Aminopyralid don’t. They are easily absorbed by unaffected plants (hay and oats) and remain chemically stable and intact through an animal’s digestive system and contaminate manure, urine and stable beds. Just imagine how much tainted urine our rice hulls have soaked up. Argh!

And what a crazy state of affairs. Sure the herbicide labels have a warning on them. Something along the lines of “Do not apply to crops that will be used for the production of compost or mulch. Such Compost or mulch made from treated plant material may cause damage to susceptible crops and plants!’ Great.
Where’s the warning on the hay? The oats? Or most importantly, the manure? What a nightmare.
Rectification of the problem has been hard, depressing work. And it’s not over yet.

All the soil in our glasshouse has now been wheelbarrowed out and replaced but throughout the patch there remains pockets of mulch, harbouring its toxins ready to nobble our next planting. Constant working of the soil is said to help leach the chemicals out but with the nasties operating at such tiny concentrations it’s hard to be optimistic.

I’m quite surprised that I’ve never come across this problem before. I’ve been warned about importing weeds to the garden by applying manures without composting them but not this disastrous situation.

Imagine how many people have been left scratching their heads wondering why their garden was struggling. I guess the best we can do is to warn others of the problem and source our manures carefully. If the horse owner doesn’t know the history of their horse feed then the manure just isn’t worth the risk. Believe me. We sure found out the hard way.

Why would you use grafted plants?

Grafting and budding are used because some seed grown plants can take a very long time to flower & fruit and then may be of poor quality after all.
Budding and grafting involves joining parts of two or more different plants together in such a way that they will grow together and continue to live as one individual plant. The top part is called the “scion” and the bottom the “stock”.

Why would you use grafted plants?

Grafting and budding are used because some seed grown plants can take a very long time to flower & fruit and then may be of poor quality after all.

Budding and grafting involves joining parts of two or more different plants together in such a way that they will grow together and continue to live as one individual plant. The top part is called the “scion” and the bottom the “stock”.


The only difference between budding & grafting is the amount of material attached to the stock.

Budding is the cutting out of a single bud with a small piece of wood backing it, then joining this to the stock (as is done with Citrus plants).

Grafting is attaching a piece of stem containing several buds to the stock.


The two essential fundamentals of budding or grafting are:-

  • the Cambiums (the growth layer just under the bark) MUST match up so that the sap can flow between the Scion and the stock and
  • the union must NOT dry out so are sealed & wrapped until the join heals.

The reason to use grafted plants is to have a much better plant that resists LOCAL insects & diseases. i.e. the root stock used in say Victoria for Citrus plants, would be different to the root- stock used in Queensland.

This a very good reason to buy your citrus plants from a LOCAL supplier (including chain stores like Woolworths & Coles) as they NOW use Local suppliers rather than buy from a postal supply nursery from Southern states because they will use their LOCAL root stock which will be different to the Queensland root stock used.

When the top part (i.e. the part that produces fruit, a specific coloured flower and /or perfume) is selected, then the root stock (the part in their ground) is usually selected for its vigour, disease resistance & tolerance of poor soil conditions. e.g. salt ,lime, water-logging, or to make the top part more compact.

Combined citrus tree

Westringia is often used as a root stock for grafting plants sensitive to the root disease of Cinnamon fungus (Phytophthora cinnamomi)

Plants from a winter rain summer dry climate, (e.g. Western Australia), are often grafted onto root –stock species more resistant to Winter dry & Summer wet climate’s conditions. (e.g. Eastern Australia).

Grevillea Robusta

Grafted plants are more expensive because they need more time & expertise to be produced compared to plants grown as cuttings or from seed.

Some Grevilleas are grafted onto Silky Oak root stock (Grevillea robusta) because that root stock is resistant to most Eastern Australian conditions of poor soil.

There are a range of grafting methods that are used but all need to be practiced often, otherwise you will loose your ability to accurately match up the Cambium tissue (the water & nutrient conducting tubes just under the bark of a plant) of the top section & the root stock.

A trailing variety of a plant is often grafted onto a standard plant so that it cascades down near eye height & so is much easier to see the full beauty of that top stock.


Another vegetative propagation method is to use Micro-propagation (Tissue Culture) where a few cells at the tip of the root are taken, kept under sterile conditions and later (up to 1 year later) taken out of the flask and potted up in a pot.

These plants are then exactly the same as the parent they came from.

With this much skilled work & time delay it can easily be seen why tissue culture plants are so expensive. It is only very special & expensive plants, e.g. prize winning orchids that are worth the effort of this type of propagation.

Today’s Did You Know…?

Some citrus plants are grafted onto dwarfing root stock so that the citrus tree can be more easily grown in a back yard, or in a big pot, and the fruit more easily picked.

There is at least one commercial fruit nursery that sells plants that are grafted so that there are two or three different types of citrus on the one root stock so a person in a backyard can have 2 or 3 types of citrus fruit in a small area.

Environmental Effects On Plants

Most of these factors are already known to us but there are other factors that we perhaps don’t consider when choosing a plant and where to plant it. And these factors are the immediate environment around where you are going to plant your plant and what effects it will have on different types of plants and during different times of the year.

Environmental Effects On Plants

Some environmental factors that affect the growth of a plant are:

  • Water
  • Temperature
  • Light
  • Nutrients
  • Hormones
  • Atmosphere
  • Soil
  • Co2

Most of these factors are already known to us but there are other factors that we perhaps don’t consider when choosing a plant and where to plant it. And these factors are the immediate environment around where you are going to plant your plant and what effects it will have on different types of plants and during different times of the year.


For instance:

A brick wall next to a plant could make a plant too hot during the day from sun reflecting off the wall onto the plant. But at night the wall keeps the plant warm as it gives back some of its absorbed warmth to the air around the plant so the plant stays warmer than other plants situated further away from that wall.

The same wall may shelter the plant from an intense storm (depending on the direction of the rain), and add extra water to the soil around the plant from water running down the wall.

The wall may also reflect light at night from an outdoor light onto the plant. This would increase the length of time that plant receives light on its leaves. If the plant is at a critical time of its flower development, the flower may not continue to develop.

A plant will flower in response to two intertwined factors.
They are ‘Day length’ and ‘Temperature’.   The term ‘day length’ is misleading as it is actually the length of night that is vital for the plant hormone in the ‘non-flowering’ form to be changed into the ‘flowering’ form. This happens during each dark event but reverts back to the ‘non-flowering’ form when light again shines on the leaves. So an external light source can greatly affect the life cycle of a plant.

In nature as days get longer and nights get shorter the length of day light time eventually equals the length of night time. This occurs twice a year in almost the middle of winter (cold) & the middle of summer (hot).
It is the combination of ‘day length’ (i.e. length of night) & temperature (hot & cold) that determines when a particular plant will initiate flowering.


Human intervention can stop a plant from flowering by using lights. Once the lights are turned off, flowering can begin. This is used by some flower growers to stop Chrysanthemums from flowering until just before Mother’s day when the demand is at its peak (& so are the prices).

In southern Australia there is winter wet & summer dry, but in the top half of the country there is a winter dry & summer wet. This adds another factor to influencing when a plant will flower in your garden.

Plants know not to flower when covered by snow or in very hot conditions unless humans have adversely influenced their reaction by interfering with their ‘natural’ mechanisms.

Nature has provided some inbuilt controls.

For example, a peach seed will not start to shoot until it has gone through a period of cold (as it would experience in a cold climate in the wild) so the new shoot is not killed by the frost.

Man can intervene by placing the seed in a fridge crisper for 6 weeks to imitate the natural cold weather but the emerging shoot needs to be artificially protected from the cold in a warmed glass-house. The extra time gained by this method is to speed up the growth in plant breeding for a new variety.


With so many factors to consider it’s a good idea to get some professional advice. Ask your local nursery man or someone you know with horticultural experience.

Your LOCAL nursery will generally keep only the plants that will do well locally. A lot of people will ask for plants that they heard about on a recent TV program without checking if the plants will thrive locally or that the presenter was talking about their location or a different location. Eg describing plants in Tasmania but the viewer is in Brisbane.

So do some research before you start planting and you will have the best chance of success in your garden.

I came across this article long after Bob had written this newsletter and it seemed fitting to provide a link here, as it talks about exactly what this post is talking about.

Today’s Did You Know…?

Researchers have proven that the plant hormone “Auxin” is the substance that makes plants lean towards the light by a process called Phototropism.

Phototropin is a pigment in the tip of growing plant shoots which is sensitive to light. It absorbs the light and releases the Auxin hormone which makes the cells grow on the shaded side of the plant.

The elongation on one side causes the bending on the opposite side.


Zeolite – The Basics

Zeolite is a naturally occurring material found in many countries around the world, as well as Australia in Northern New South Wales.   It is very low in nutrients but contains some Potassium, a small amount of Calcium and is known to have a very high Cation Exchange Capacity (see Did You Know section below).

Zeolite – The Basics

Zeolite is a naturally occurring material found in many countries around the world, as well as Australia in Northern New South Wales. It is very low in nutrients but contains some Potassium, a small amount of Calcium and is known to have a very high Cation Exchange Capacity (see Did You Know section below). A high grade more pure form can be made in a laboratory for such uses as cleaning air supplies for pilots. This is termed a medical –grade oxygen.

Is Zeolite readily available?

Zeolite is mined, ground up, then bagged for sale as a natural garden additive. Because it is a natural product not all deposits have the same range of purity, so the quality is reflected in the price.


What is it used for?

Zeolite has many uses apart from Horticulture and general gardening. It is also used in many every day products some of which include:

  • Kitty litter where it is super absorbent as well as holding odours so it acts as a deodorant in the non-clumping form
  • Pool filters instead of sand to collect pollutants
  • Water purifiers removes toxic wastes from water & fly ash
  • Nuclear Absorbent used with the Fukushima Disaster
  • Odour neutraliser removes odours and freshens air (e.g. under chicken pens)
  • Vermaculture (Worm farming) absorbs heavy metals, and stabilises the pH level
  • Washing Powder and Detergents. This is the largest single use for Zeolite
  • Cement as an additive – to make it easier to work with

In Horticulture

Zeolite is used to absorb and hold nutrients and water but also allows plant roots to absorb the dissolved nutrients from the Zeolite for their growth.

Some of the uses in Horticulture are:

  • Turf – Zeolite is mixed with the soil before any turf is laid at the rate of 250 -750 grams per meter of soil. For existing lawn, the Zeolite is applied after the lawn has been aerated, and is often mixed with fertiliser and/or sand at 250 to 1kg per square metre of soil.
  • Garden beds – Zeolite is generally mixed into the top 10-15 cms of soil together with any organic manure or other fertiliser to improve water holding capacity and nutrient retention.
  • Planting – Zeolite can be put into the bottom of the hole, mixed with the soil then the new plant installed
  • Compost heaps – Zeolite can be used to control the leaching out of Nitrogen by absorbing Ammonia which it then converts to Nitrogen delivering nutrition to plants on demand. It is in this process that Zeolite acts as an odour reduction agent or absorber
  • Mulch – Zeolite is normally used to retain moisture and nutrients. It can minimise splashing of fungal spores onto plant foliage from the bare soil. This helps with reducing plant root rot from Fungi like Phytophora spp
  • Potting mix – Zeolite reduces the added amount of fertiliser required (especially Nitrogen) because it retains nutrients that would otherwise be lost through the leaching process.
    *When Zeolite is used in Horticulture it is primarily from a natural source so it is generally accepted as an organic material for the certification process.

Health and Safety

Zeolite is not toxic in itself; it is the milling process turning it into a fine texture that the user needs to be aware of. It is recommended that a mask be used to stop it entering the mouth and lungs which may cause irritation.

Some people have been know to ingest Zeolite to soak up Alcohol after a big night of drinking. Supposedly you don’t get a hangover.


Today’s Did You Know…?


There are seven cations in the Cation Exchange Capacity.      These are positively charged particles that measure and influence the soils ability to hold on to essential nutrients.

They are

  • Hydrogen (H)
  • Aluminium (Al)
  • Calcium (Ca)
  • Magnesium (Mg)
  • Potassium (K)
  • Ammonia (NH4)
  • Sodium (Na)

So here’s how it works
The Cations (positively charged nutrients) are attracted to Colloids (negatively charged particles) of soils and other material. These colloids are basically a food storage facility for nutrients that plants can access when they are released (or exchanged) into the soil water. These cations (nutrients) in solution are now available for the plant to use. The ability of each particle (colloid) to hold cations (nutrients) is limited by the number of negative charges they hold on their surface.





“If there is a concentration of one particular Cation in the soil water, those cations will force other cations off the colloid and take their place.
The stronger the colloid’s negative charge, the greater its capacity to hold and exchange cations, hence the term Cation exchange capacity (CEC).”


Zeolite has a very large Cation Exchange Capacity Go to for more information