Nutrients - Soil Additives




Following on from previous issues Paul Plant investigates the role of soil additives that enhance the organic garden.

Charcoal is created by slow burning vegetation in a condition where oxygen is limited, a process known as pyrolysis. It is a traditional technique of adding carbon to the soil in order to boost soil fertility in a number of ways – attracting microbes, trapping moisture in its tiny pores and retaining soil nutrients for plant and crop use. The claims credited to charcoal use are increased crop yields and productivity with the added benefits of reducing leaching and minimising surface water run-off.
Though this may sound like a new trend to some people, forms of charcoal have been added to the soil thousands of years ago in the Amazon basin and other parts of South America. These neglected but highly fertile soils known as Terra Preta do Indio were noted to be high in carbon, rich in phosphorus and potassium.

Selenium (Se) is regarded as an important mineral for human and animal health. It is only needed in minute concentrations and consequently an understanding of this mineral in the soil and its impact on the growth of ornamental plants and vegetables has gained interest.

From a 2 page Feature Article in Issue Seventeen
Botanical Alchemy…Companion Planting

By the Northey Street City Farm


The below item complements this article read in the current issue:

Botanical Alchemy…Companion Planting (pp. 50-51)

Botanical Alchemy Supplement




Companion planting is a little mysterious. Is it science? Is it alchemy?
Is it witchcraft? Perhaps it’s a little of all three. It is just one of the tools employed by organic gardeners and permaculture designers that is based on hundreds (maybe even thousands) of generations of gardeners’ observations and trial and error.

While some maintain it has no scientific basis at all and therefore not worth the effort, others swear by it. There is, as yet, little published scientific evidence on the mechanisms and chemistry of companion planting, although there is much recorded on plant associations that do work and result in more productive gardens than if each plant were grown in isolation.


  • How does companion planting work?
  • Companion plant / Companion function
    • Amaranth (Amaranthus retroflexus)
    • Basil (Ocimum basilicum)
    • Bay Laurel (Laurus nobilis)
    • Borage (Borago officinalis)
    • Calendula (Calendula officinalis)
    • Lawn Chamomile (Chamaemelum nobile; syn. Anthemis nobilis)
    • Chives (Allium schoenoprasum)
    • Clover (Trifolium species)
    • Comfrey (Symphytum officinale)
    • Coriander/Cilantro (Coriandrum sativum)
    • Dandelion (Taraxacum officinale)
    • Feverfew (Tanacetum parthenium)
    • Garlic (Allium sativum)
    • Lemon Balm (Melissa officinalis)
    • Lemon Verbena (Aloysia citriodora; syn. Aloysia triphylla)
    • Lovage (Levisticum officinale)
    • Lucerne/Alfalfa (Medicago sativa)
    • Marjoram (Origanum majorana)
    • Mint (Mentha species)
    • Mulberry (Morus species)
    • Nasturtium (Tropaeolum majus)
    • Oregano (Origanum vulgare)
    • Rosemary (Rosmarinus officinalis)
    • Pineapple Sage (Salvia rutilans; syn. S. elegans)
    • Tansy (Tanacetum vulgare)
    • Valerian (Valeriana officinalis)
    • Wormwood/Absinth (Artemisia absinthium)
    • Yarrow (Achillea millefolium)

Companion planting is about holistic gardening – about seeing the garden as a complete cooperative system that is more than the sum of its parts. While the effort involved in researching companion planting requires planning and research and may be time consuming, the benefits may well compensate and will save work and expense over time.

From a 2 page Feature Article in Issue Seventeen
Yarrow (Achillea millefolium).
Calendula (Calendula officinalis).


The below item complements this article read in the current issue:

Chokos (pp. 52-55)

Chokos Supplement




The Choko would be one of the most well-known vegetables grown
in the warmer parts of Australia. The vines once graced almost every garden – often planted over the famous outdoor dunny.

Choko plants are famous for their amazing productivity. The vegetable is also infamous for its flavour – or lack of it. There is a generation of Australians who associate this vegetable with meals they would rather forget. Luckily the standards of vegetable cooking in this country have improved significantly since the 1970s and a new generation of gardeners and cooks are discovering how amenable the Choko is when used in a variety of dishes.

The Choko (Sechium edule) is a member of the cucurbit family (Cucurbitaceae) along with Pumpkins, Squashes, Marrows, Zucchini, Cucumber and Melons.

From a 4 page Feature Article in Issue Seventeen
Custard Apple

By The Sub-Tropical Fruit Club of Queensland


The below item complements this article read in the current issue:

Custard Apple (pp. 56-59)

Custard Apple Supplement




The Custard Apple, with its irregular bumpy light green skin, may not be
that appealing to the eye and it is nearly always one of the more expensive fruit at the super-markets, but do not let this put you off this scrumptious fruit. It is perfect for eating every day for those with a sweet tooth. The fruit also has fibre and other nutrients making it low GI and more filling than other sweet foods.

Try giving some mashed flesh to toddlers or in a smoothie for children and you will find it is a fresh and healthy alternative they will want time and time again.

Topics featured are:

  • Popular Home Varieties
  • Overcoming Fruit Setting Problems
  • Inducing Flowering
  • Cultural Requirements
  • Harvest
From a 4 page Feature Article in Issue Seventeen
Custard Apple. Image Horticulture Australia.
‘Tropic Sun’ – the soon to be  released variety.
Warrigal Greens

By the Queensland Bushfood Association

Download the Bushfood Recipe as found on p.61 of STG Issue 17.

Bushfood 17




Warrigal Greens (Tetragonia tetragonioides), is one of a few species of native plants that can be used as a green vegetable. It is also known as Native Spinach, Botany Bay Greens and New Zealand Spinach. It is a popular tasty green, worthy of inclusion in a variety of dishes.

Captain Cook fed this plant to his crew to prevent scurvy and Joseph Banks sent the seed to England in 1772, where it became a popular ‘pot herb’ and eventually throughout Europe by the 19th Century. The Warrigal Greens was one of the first native plants recognised for its food potential by early European settlers.

Naturally occurring over a wide range of soil and climatic conditions, Warrigal Greens is common in protected coastal dune areas and on the margins of inland salt marshes. It may be confused with the related species, T. implexicoma that contains far more oxalates, is less tasty and not recommended for food.

From a 2 page Feature Article in Issue Seventeen
Warrigal Greens in a raised garden bed. Image Doug Brownlow.
Warrigal Greens flower close-up. Image Graeme White.
Feeding Chooks




A lot of people have the misconception that poultry can be fed on kitchen scraps and a bit of free ranging alone, thinking that they do not require any other form of food. This is not true.

It is true, however, that the average chicken in the average yard or paddock would definitely gain a large quantity of their required dietary needs from foraging, especially in the form of greens, protein from insects and grit from the dirt.

It is important to provide a complete commercial poultry feed.

Chickens are relatively easy to feed and for the volume of food required, are surprisingly productive. Of course chickens are great at demolishing any leftovers from last night’s dinner, but just remember that these treats alone will not suffice.

From a 2 page Feature Article in Issue Seventeen
Buff Silkies
Silver Spangled Hamburg.
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