Lesson 2 culture of native plants

What about wound treatments?

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What about wound treatments? 

Fungicide treatments painted over a wound may in theory deter the growth of disease. Scientific advice 

seems to suggest that wounds do not become more infected if you don’t paint them - dark paints, 

however, can make the wound less obvious. 




Some native shrubs will take relatively hard cutting back, but many will not. If you don't know a plant, you 

may be taking a grave risk by heavily pruning it. 

  Many wattles tend to die back if pruned too heavily, though sometimes the same variety will re-grow 

rapidly after a heavy cut. You cannot always predict if the plant will take a heavy pruning. 

  In nature, shrubs tend to be "nibbled" constantly by native animals. Similarly, most natives respond 

well to frequent light pruning. The safest way to prune native shrubs is frequent light tip pruning, 

rather than occasional heavy pruning. 

  There are exceptions. Some natives respond to heavy pruning. Red boronia (B. heterophylla) will 

actually live longer if flowers are harvested in a heavy pruning every spring. 




Requirements are diverse, and there are Australian natives that will grow out doors in most populated 

parts of the world from cool temperate zones to the tropics.  If you live in a colder climate the following list 

may provide some guide as to what could be worth trying out. 


Frost hardy native plants 

Acacia baileyana, cultriformis, dealbata, floribunda, pravissima 

Allocasuarina cunninghamiana, glauca, stricta, torulosa 

Banksia ericifolia, marginata, media, spinulosa 

Bauera rubioides, sessiliflora 

Boronia filifolia, megastigma, muelleri, pinnata 

Brachyscome multifida 

Callistemon citrinus, pallidus, paludosus, rigidus, salignus 

Callitris oblonga 

Cassia artemisioides, sturtii 

Correa alba, decumbens, manni, reflexa 

Epacris impressa, microphylla, pulchella 

Eremophila glabra, maculata 

Eriostemon myoporoides, verrucosus 

Eucalyptus cinerea, cladocalyx, crenulata, gunnii, leucoxylon, macrandra, melliodora, nicholii, pauciflora, 

polyanthemos, sideroxylon, stellulata. 

Grevillea alpina, aquifolium, baueri, capitellata, confertifolia, juniperina, lanigera, lavandulaceae, Poorinda 

hybrids, rosmarinifolia, sericea, steiglitziana, tridentifera 

Hakea elliptica, nodosa, petiolaris, purpurea, salicifolia, sericea 

Helichrysum apiculatum, baxteri, bracteatum 

Indigofera australis 

Kunzea capitata, parvifolia, pomifera 

Leptospermum flavescens, humifusum, juniperinum, lanigerum, scoparium 

Melaleuca decussata, elliptica, incana, pungens, squarrosa, stypheloides, thymifolia, uncinata, wilsonii 

Myoporum parvifolium 

Pandorea pandorana 

Pittosporum phyllyraeoides 

Prostanthera aspalathioides, crenulata, lasianthos, nivea, rotundifolia 

Telopea oreades, speciosissima 

Thryptomene calycina, saxicola 

Westringia fruticosa 




The first step is to prepare the soil and to remove any weeds (see sections on improving soils and weed 



Basic planting procedure 

Plant most containerized plants as follows: 


1.  Thoroughly soak the plant in the pot, to help the plant come out of the pot easier; and allow it to drain. 

(Ideally, immerse the root ball in water until air bubbles stop rising eg. dip it in a bucket or tub of water). 


2.  Dig a hole one and a half times the depth of the pot, and in hard soils, break up the soil well at the 

bottom and sides of the hole. 


3.  Place a small amount of slow release fertiliser in the hole. 


4.  Fill in one third of the hole and mix the fertiliser with the back filled soil. 


5.  Take the plant out of the pot. Turn upside down and tap on the side of a wall or other hard object: and 

it will slide out easily. 


6.  Loosen any exposed roots.  (ie. if most of the roots are inside the soil ball, you might not need to do 

much.  If there is a tight mass of roots on the outside of the soil ball you may need to break a centimetre 

or so into the ball all over).  Free any roots circling the bottom of the container. 


7.  Place the plant in the hole and cover with soil.  Firm down but don't compact to a hard impenetrable 

surface. Make sure that the surface of the potting mix is at the same level as the ground surface. Don't 

bury the trunk/stem, as this can affect the success of some plants. 


8.  Make a lip of soil around the base of the plant to hold water. 


9.  Soak thoroughly with water. 


10. Mulch with a suitable material. In hot or dry conditions mulch should be thick enough, and extend far 

enough from the base of the plant to keep roots cool, and minimise evaporation from the soil. 



Time of planting 

Planting is best timed to allow plants to settle in and establish before facing the harshest time of the year. 

The harshest time of year will vary from place to place, and may also vary according to the plant species 

being planted. 


In temperate climates, planting may be done at any time of the year providing the plant will receive 

adequate water. In well maintained gardens, planting may be done when growing conditions are optimal 

ie. in the southern states planting is best done in autumn or spring when rainfall is high, and there is 

adequate warmth in the soil to stimulate root growth. 


In tropical or sub-tropical climates planting may be better carried out after the hottest part of the year, but 

while the ground is still moist. 


In areas with severe frosts planting may be best carried out in spring after the threat of frost has passed. 

This will give the plant time to establish before the following winter. 


Always avoid planting on hot or windy days - plants are more likely to dry out in these conditions. 

Always avoid planting just prior to severe storms which may damage young plants. 



Staking is not always necessary. It can in some cases do more harm than good. When movement of a 

plant in the wind is stopped completely, it may not develop sufficient strength in the trunk (known as 

"reaction wood") to withstand the wind when the stake is finally removed. 

Plants SHOULD be staked if they are likely to fall over (ie. because they are exposed to severe winds), or 

if they are likely to suffer from vandalism or unintentional damage. A tree guard may alternatively be used 

(surrounding the plant with a tube or wall), to protect it from wind, vandalism, or foraging animals.  


When you do tie a plant to a stake, the tie should be loose allowing the plant to move about in the wind.  

If movement is restricted, the tree may never develop proper strength in its join between the roots and 

trunk. Be sure to check as the plant grows that the tie is not restricting the growth of the plant.  


Stakes can also be used simply as a marker (without ties) for small plants that may overgrown by grass, 

before they have had a chance to get established and put on a spurt of growth. This makes them easy to 

locate when you are mowing, trimming, etc. 



Mulching has several advantages as follows: 

  Helps control weeds. 

  Conserves soil moisture (helps prevent drying out). 

  Improves soil structure. 

  Adds nutrients to the soil. 

  Reduces fluctuation in soil temperature. 

  Can promote earth worms. 

  Can reduce soil erosion. 


Almost anything organic can be used as a mulch.  Here are just a few examples: wood-shavings

sawdust, tan bark, pine bark, leaf mould, paper, old rags, compost, straw, pruning material, weeds, lawn 

clippings, leather, cardboard, etc.  There are even some inorganic materials which are useful as mulches, 

including gravel, scoria, blue metal, coarse sand, and river pebbles.  


Wind can be a problem, blowing away some fine mulch when they are first delivered, or laid down (eg. 

wood shavings). Once thoroughly wet and settled however, even these mulches tend to stay where they 



All too often, the desired benefits of the mulches are not achieved.  



Some common mistakes are: 

  Mulch is not thick enough.  Different types of mulches should be applied at different thicknesses ie. 

30mm for fine mulch and 60-80mm for coarse mulch 

  Black plastic placed under mulch will create an impermeable layer, causing plants to suffer from 

water stress. Sweating underneath may cause water to stagnate, creating foul smells and promotion 

of root diseases. 

  Weeds need to be eradicated BEFORE the mulch is laid. Weeds can be removed by hand or a 

non-selective, non-residual weedicide eg. Roundup (Zero) can be sprayed several weeks before 

laying the mulch.   

  Maintenance is often ignored. Top up organic mulches regularly; remove weeds before they develop 

seed heads. 

  Wood-shavings (and some other mulch) need to be kept moist for the first month or two.  This will 

allow the mulch to "settle" and prevent the wind blowing away large amounts of material. 

  As organic materials decompose, they draw on nitrogen from the soil. Plants which are grown in 

mulches made from shavings, wood chips, and paper may show nitrogen deficiency symptoms (ie. 

the leaves will turn yellow).  To counteract this, apply a small nitrogenous fertiliser. 

  Mulch has not been thoroughly wet when first laid down. Many organic materials actually repel water 

when they are dry. If it is not moistened through when used, rain can run off the surface to the sides 

of the plants. 





Most home gardeners shouldn't have too much difficulty in establishing new plants. In some areas, 

however, problems such as severe soil erosion, arid climate, etc. will mean that special techniques are 

needed to enable the plant to establish in its new environment.  


Pocket planting 

This is simply establishing a pocket or basin on a slope, with the soil excavated from the pocket being 

used to form a wall enclosing the pocket, particularly on the down slope side. The wall will then retain 

water and help prevent soil erosion occurring.  An overflow spillway in the wall will prevent the pocket 

from being washed away in heavy rains.  The pocket may need to be reformed every now and then, until 

the plant is established. 


Slope serration 

Sloping sites can be terraced to enable plant establishment and reduce erosion.  Slopes are cut into 

steps which measure approx. 1 m wide, with the steps sloping back towards the hill to retain water. Over 

time, the steps will erode however the plants will usually have become established by then.  The loose 

soil from the eroded steps also provides favourable germination sites for seed which is dropped from 

other nearby plants. 



This technique relies on the use of bunches of branches placed on slopes to prevent erosion.  Bundles of 

long, slender branches are tied into bundles and are partially buried in contoured trenches which have 

been cut across the slope, or cut branches and dried brush are simply spread across the surface of the 

slope. 'Chicken wire mesh' or strands of fencing wire are sometimes pegged down on top of the branches 

to hold them in position. (Some types of wire mesh can lead to zinc toxicity, particularly on moist soils). 

Layers of straw or commercially available synthetic matting can be used to similar effect. 


This technique has been more commonly used overseas, although it can be used here on badly 

degraded sites to enable native species to regenerate.  In Australia, dried brush is more commonly used. 

This type of brush material: eg. Leptospermum often contains large quantities of capsules that release 

seed; which will often readily germinate on the newly stabilised slope. 





The following points are general comments about natives and shouldn't be considered iron clad rules. 

(There are exceptions.) 

  Don't feed natives with fertilisers which contain a high percentage of phosphorus (including super-


  Don't break the tap root on native trees when planting them. 

  Tall native shrubs and trees do not transplant well. 

  Many natives require good drainage (it is a good idea to plant them on a raised mound of soil). 

  Mulching is generally desirable, to keep roots cool and minimize water loss in summer. 


To grow plants is more than just planting and standing back! Even our so called "hardy natives" require 

ongoing care if you want to get the best from them. 


Planting arid sites 

Plant establishment in un-irrigated, arid sites can be extremely difficult. Mulching, controlling competing 

weed growth, wide spacing of plants and creating saucers of soil to retain water, are simple ways of 

overcoming the water shortage problem.  Smaller sized plants also have a better chance of becoming 



Condensation traps have also been used with some success in areas with clear night skies.  One simple 

method of trapping the moisture from condensation is to construct a 1.5 m diameter planting basin with a 

depth of 30 cm. The plant is placed on a mound in the centre and polythene sheeting is arranged to 

collect evaporating soil moisture, which condenses on the sheet and drips back to the ground. 


Direct seeding 

Direct seeding is a low cost method of re-establishing vegetation, although the results are less 

predictable than transplanting established nursery- grown plants. 


The most important factor is to eliminate weed growth before seeding to remove competition from the 

germinating seeds. An initial spray with chemical herbicides will give the best results; alternatively 

cultivation can be used to encourage dormant weed seeds to germinate which can then be sprayed. A 

light cultivation of the soil will also provide favourable germination conditions for the seed.  Seed can then 

be broadcast either by hand on small sites, or by direct drilling or mechanical hoppers for larger areas. 

Fencing the site and follow-up weed control may also be required. Irrigation or timing of seeding to make 

the best use of rainfall will help germinating seeds to get a good start. 


In areas where there is an existing cover of native vegetation, natural regeneration can give good results.  

The site should be fenced off, and the weeds on the windward side of the tree (where seeds are most 

likely to drop) should be removed. 



Shade can cause a range of different problems for plants and gardens: 

  Reduced light can restrict plant growth. Many plants in shaded areas will appear weak and leggy, 

with poor flowering.  

  Shaded areas are cooler than adjacent open areas. Whilst this is generally a benefit to the garden, 

growth in shaded areas may be slow in cool climates (eg. this may be more of a problem in Hobart 

than Sydney). 

  Shade encourages the growth of moss and algae on the ground (including paths), making them 


  Water in shaded areas does not dry up so readily. 

  Roots from large shade trees compete with smaller plants growing below them. 

  Soil under trees can be quite dry, as the overhanging leaf canopy prevents water penetration. 

  Foliage from some trees (eg. conifers) may be toxic to plants below. 

  Roots of some trees may give off toxins which inhibit growth of other plants (eg. Eucalyptus trees). 

  Leaf or branch drop from trees may smother or damage low-growing plants below. 

  Trees restrict ventilation (ie. air movement), which may encourage disease problems in shaded 



Plants suited to full shade 

Boronia mollis 

Dampiera diversifolia 

Epacris impressa  

Kennedia prostrata 

Thryptomene spp. 






Other shade tolerant natives 

Acacia mitchellii 

Acacia myrtifolia 

Acacia terminalis 

Calytrix spp. 

Dryandra spp. 

Eriostemon (most varieties) 

Eucalyptus camaldulensis 

Eucalyptus globulus 

E. gompocephyla 

E. polyanthemes 

E. radiata 



Rainforest plants 

Rainforest trees and under-storey plants are well adapted to low light situations. For these reasons, many 

are used as indoor plants when young then planted out when too large for the home. 

Some rainforest species that tolerate dark conditions include: 


Agathis robusta                 

Ardisia pachyrrhachis 

Castanospermum australe         

Cissus antartica 

Cissus hypoglauca               

Cordyline spp. 

Cryptocarya erthroxylon        

Davidsonia pruriens 

Dracaena angustifolia           

Eupomatia laurina 

Ficus spp.                      

Harpullia rhyticarpa 

Phaleria octandra               

Podocarpus elatus 

Randia fitzalanii               

Schefflera actinophylla 

Stenocarpus sinuatus           

Wilkiea angustifolia 



Many Australian rainforest palms will handle low light positions but will do better if provided with dappled 

light. Archontophoenix species are hardy in dark situations but grow better in bright light to full sun when 




Ferns are ideal for growing in shady areas as they are naturally adapted to growing in conditions of low 

light.  Different varieties can tolerate different levels of shade and soil moisture, so use the following lists 

to choose ferns which suit your particular problem area.  


Hardy with some shading in the hottest part of the day: 


Davallia trichomanoides, 

Pellaea (most species), 

Pteris cretica,       

Doodia media, 

Platycerium (most species), 

Pteris vittata         

Dryopteris erythrosora, 

Polypodium aureum, 

Nephrolepsis cordifolia,  








There are 2 different types of weeds; annuals and perennials. 


ANNUAL WEEDS grow from a seed to full maturity within 12 months. If you can stop seed being 

produced, then the old plant dies and there are no seeds for new plants to grow from. 


PERENNIAL WEEDS persist from year to year, if you kill off the top but not the root, they might very well 

re-grow from the root. 


Weed control methods 

Although weed populations and density can be 

reduced through weed prevention, it will not 

completely eliminate them. A weed control program 

should be used in conjunction with the preventative 

measures outlined above including 


  Mulching – smothers weeds (covered earlier 

this lesson). 



– hand cultivation through hoeing or 

hand pulling although time consuming is 

reasonably effective. Mechanical cultivation 

should be minimised in an organic system to 

prevent destruction of soil structure and spread 

of perennial weeds propagated readily from 



If native grasses or groundcovers can be 

established under a canopy, weed growth  

can be suppressed 


  Mowing - cutting the tops from the weeds regularly depletes the weeds food reserves. Mowing should 

be carried out before seed set in both annual and perennial weed species.  The cut foliage should be 

left to rot and return nutrients back into the ground. If the weeds are tall when cut, the foliage will act 

as mulch, slowing re-growth of weeds.  

 Solarisation - large sheets of clear plastic are spread over the surface of the ground in warm weather. 

Heat generated under the plastic can be great enough to kill many types of weeds. The plastic can 

then be removed (perhaps after a couple of weeks) and the area planted. This technique will also 

often kill other pest and disease organisms. Note that this method is only suited to warm climates that 

can depend on two or so weeks of continuous sunshine.  

  Flame Weeding – flaming is only effective on annual weed species and weed seeds beneath the 

soil surface are rarely killed. May be


effective way to control weeds along fence lines (with care) or 

on pathways and gravelled areas.  

  By chemical methods - some chemicals (eg. Weedex) will burn off the top but not kill the weeds. 

Some chemicals move throughout the sap system of the weed, killing every part of the plant (eg. 

Zero). This type of chemical needs to be used with particular care as it will kill plants you want to keep 

if you let it touch them. Some chemicals kill one only type of plant (eg. broad-leaved weeds in lawns) 

without killing other types of plants (eg. grasses). 

  By competition - if the desired plant is healthy and vigorous, it will naturally compete with the weeds.  

  By biological control - using living organisms to attack or eat the weeds (eg. grazing animals, certain 


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