Armidale District

APS Armidale Fact Sheet - Care of Plants

1. Practical Tips and Tricks


Marcia's Plant Tonic

Banksia Spinulosa

ABC's Saturday gardener Marcia Ajani has some great little tips for the home gardener, which are always in high demand.

This is her plant tonic:

  • 1 teaspoon liquid seaweed and fish fertiliser (seasol &/or fish emulsion)
  • 1 teaspoon sulphate of potash
  • 1 teaspoon magnesium sulphate(epsom salts)
  • 1 teaspoon sulphate of iron (or iron chealate)

Mix in 5 litres of water, and spray it on the plant until saturated.

Thank you Marcia. - return to index

Marcia's Powdery Mildew Remedy

  • 1 Litre Milk
  • 1 Litre Water
  • 2 tablespoons Bicarbonate of Soda

Mix together and spray on affected plants. You may need to repeat at intervals.

Thank you Marcia. - return to index

To Prune or not to Prune


Australian plants are no different to exotic plants when it comes to pruning and many respond well when pruning is carried out. In the bush many are naturally pruned by wildlife such as kangaroos and wallabies.

Flower production is usually increased quite dramatically after pruning. Some short-lived plants can have their lives extended by pruning. Increased foliage density resulting form pruning allows better protection for wildlife, also nesting sites for our smaller birds. Desired form and shape can be controlled by judicious pruning.

Micro Pruning: Constant tip pruning is probably the best for many plants. This is carried out by pinching out the tips by holding them between the forefinger and thumb. It is advisable to begin this method while the plants are seedlings or rooted cuttings and continued after planting. This usually provides a good framework and some plants will not require heavier pruning later.

Macro Pruning: Most Australian natives flower on new wood. This heavier pruning is usually carried out in late spring after flowering has finished, cutting behind the spent flowers.

There are some plants that flower on old wood and care must be taken otherwise they will not flower for some time, eg Calothamnus.

Hedges require light pruning to maintain shape.

If in doubt whether a plant can handle pruning or not then cut back only half the plant. Responses by the plant will determine if the remainder can be pruned.

Very heavy pruning, coppicing, that is the removal of plant growth just above ground level, can be carried our particularly for eucalypts. Those with a lignotuber respond best. Not all eucalypts respond positively and it is best to check before pruning.

  • Acacia: Light
  • Banksia: Light
  • Calothamnus: Light pruning but not into old wood
  • Callistemon: Moderate behind flower heads
  • Calytrix: Light
  • Correa: Light
  • Dodonea: Most respond well but not into old wood
  • Eriostemon: Light
  • Eremophila: Light
  • Eucalyptus: Tip prune if more lateral branches are required. Coppicing for mallee effect
  • Grevillea: Light to heavy depends on species. Parrots love their seeds so leave some branches unpruned
  • Hakea: Light to moderate if required
  • Kunzea: Light to moderate
  • Leptospermum: Most respond to light pruning
  • Melaleuca: Moderate to heavy depending on species
  • Myoporum: Light pruning. Myoporum floribundum do not prune into leafless wood
  • Olearia: light but not into leafless wood
  • Prostantheras: Light but not into leafless wood.

Gloria Sheather, November 2006 - return to index

Twenty Facts about Mulches - Kevin Handreck SA


[This article is taken from the Garden Design study Group Newsletter No. 58, May 2007, and was previously published in 'Gardening Australia', page 74, November 2005]

In nature, virtually all soils have a mulch on their surface. The soils of forests have litter and leaf mould; those of grasslands have a layer of decaying grass and mosses; many desert soils have a stony surface; the sand of sandy deserts is an excellent mulch.

In our gardens we use mulch as a substitute for these vital natural soil covers.

  • Look at the organic litter on a forest soil. It grades from very fine highly decomposed humus at the soil surface to the coarseness of recently fallen leaves and twigs on top. In our gardens the ideal mulch will be like that.

  • The most important property of a garden mulch is that it should reduce the rate of water evaporation from the soil below.

  • A mulch is like a blanket on the soil. The best mulches allow rain or irrigation water to move into the soil below, but they minimise the loss of water by evaporation. They reduce evaporation partly by providing a break between soil water and air. Water is not then simply 'sucked' out of the soil by the sun and wind. It has to pass as a vapour through the still layer of air within the mulch and this is much slower than direct evaporation.

  • Many of the organic mulches available in retail packs are too fine to be of top effectiveness. A thick layer (eg 50 mm) of fine mulch will hold most of the light rain that falls on it; only with heavy rain will the water actually reach the soil. There is no break between water and air so water wicks up through fine mulches. The rate of water loss from fine mulches can in fact be higher than that from bare soil.

  • In good mulches most of the particles will be larger than about 5mm. Only a small proportion will be smaller than 2 mm. The high the proportion of 'fines', the less effective will be the mulch in reducing water loss.

  • Loss of rain or sprinkler water from fine mulches can therefore be faster than that of bare soil. But if most of the water is applied below them (by drippers or soaker), they will reduce evaporation rate.

  • Fine mulches are excellent seed beds for weed seeds that are blown into the garden.

  • The large particles of coarse mulches will gradually decompose, so that after several years of additions, the earlier additions will have decomposed to be like fine humus of the bottom layer forest litter. The later additions will be doing the work of reducing evaporation. To speed up this process on a new bed, you could first apply a thin (eg 10 mm) layer of fine mulch and then a thicker layer (eg 40 mm) of coarse mulch that has few fines.

  • In summary the best benefit is obtained from water by applying irrigation beneath a coarse organic mulch.

  • Organic mulches are living mulches. They are gradually decomposed by small soil animals, fungi and bacteria. In the process nutrients are released for use by the plants.

  • But in addition plants actually help themselves to the nutrients in the mulch. Most plant roots have beneficial fungi (Mycorrhiza) growing on them. These fungi send out hyphae into the lower layers of leaf mould where they secrete acids and enzymes that dissolve nutrients such as phosphorous and take them back to the plant.

  • Proteaceous plants do the same thing by producing clusters of fine roots in the humus layer. If you repeatedly remove leaf litter from a garden bed, you are robbing you plants. Poorer health and growth are inevitable.

  • Another benefit of mulches is that they protect the soil from the pounding of rain and irrigation water. On sloping ground soil erosion is minimised.

  • Mulches also shade the soil below. In summer the lower temperature under an organic mulch allows roots to continue to grow into the topsoil.

  • But in winter mulched soil will tend to be cooler than bare soil and plant growth may be slightly reduced and the effects of frost severe.

  • Any problems? There can be, but they are minor compared with the benefits.

  • Uncomposted 'waste' material may contain weed seeds, may be temporarily toxic to plant roots and can reduce oxygen supply to plants for some months. Composting kills weed seeds and eliminates toxicity. Some extra nitrogenous fertilizer should be applied to woody mulches.

  • If you find that repeated heavy mulching produces water repellence in you soil, overcome this in the short term with a wetting agent; reduce applications.

  • Organic mulches are the best, but what about non-organic mulches (stones, crushed rock etc). These can give interesting decorative effects, but they are difficult to maintain in good condition. Fallen leaves have to be removed, so the benefits of the leaves to the plants is lost.

  • Plastic sheeting must not be used a s mulch. Unless it has holes punched into it, neither water nor oxygen can move into the soil below. Plants will be harmed. If you do want to use palstic, use woven products such as weed mat, whose holes allow water and oxygen to pass.

Kevin Handreck is the author of the book "Gardening Down-Under" (CSIRO).

- return to index

Inoculant "MycoGrow"

Onions grown with MycoGrow.

At the Wattle Day function (September 2007) it was suggested that we buy a bag of this product and share it among members at the next meeting. The innoculant is broad spectrum and has been shown to improve the growth of Eucalypts and Acacias by three (3) times in the local area.

We thought it might be good to experiment with it on a range of native plants, such as all the legumes and Myrtaceae. It may also benefit other genera. All Mycorrhiza have a short shelf life (a few months) so it needs to be used up this growing season.

MycoGro VA Mycorrhiza (VAM)

MycoGro inoculant is a fine dry powder containing Vesicular Arbuscular Mycorrhiza (VAM) of the species Glomus intraradices. Live fungal spores and propagules. A minimum of 250,000 spores or propagules per kilo of carrier.

VA Mycorrhizas or VAM - What are they?

VA Mycorrhizas are fungi that grow as minute filaments that attach and penetrate the roots of most plants.
VAM Myco-Gro improves uptake of water, improves uptake of nutrients, improves soil structure.
Myco-Gro inoculant must come into contact with the growing root to be effective.

MycoGro can be applied:

  • To small fruit trees, roses, grapes: Dipping damp roots into the powder or sprinkling the powder on to damp roots.
  • To tree transplants: Sprinkling into the planting hole or side dress (band) the powder into the planting row during planting.
  • To freshly transplanted strawberries, tomatoes: Suspend powder in clean water and deliver evenly to each plant.
  • By water into turf and golf greens.
  • By mixing into planting soil before potting.
  • By adding to compost tea prior to application.

Maria Hitchcock, October 2007 - return to index

Tamara's Cut Flower Preservative

from Tamara Cox - East Hills Group (on Tasmanian Conference) 2004:

Concentrate Mix

  • 400 grams sugar (2x250 ml cups) dissolved in 1400 ml boiling water
  • Add: 20 grams citric acid powder (1 teaspoon)
  • 250 ml (1 cup) household disinfectant

Top up with water to make 2 litres.

Application Mix

  • Use 100 mls of concentrate to 1 litre of water.

  • Concentrate keeps for many years
  • Store concentrate in a glass container, as it seeps through plastic.

Thank you Tamara. - return to index