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The following have been selected from the questions received on the SGAP World Wide web site over the past few months. You're welcome to comment on any issue concerning Australian native plants....growing, propagating or appreciating (even loathing!) ... anything.

If necessary, bung a message in a bottle if your net connection goes down!!

....and, if you'd like to contact any of the correspondents and no email address is listed, please feel free to do so through the editor.

Hedging Your Bets!

Which native plants can be grown as hedges?

C & M Cheesman

There are quite a few. Basically, any plant which responds to regular pruning can be used as a hedge. If you can get hold of the book "Encyclopaedia of Australian Plants - Vol 1" by Elliot and Jones, the section on "Screening plants to 2 m" on page 307 will be useful. This book is held by many municipal libraries.

Some of the new Syzygium cultivars are claimed to be ideal hedges. Some that I am aware of are:

  • S.australe "Tiny Trev" - 75cm
  • S.australe "Blaze" - 1.5 m; bright red new growth
  • S.australe "Bush Christmas" - 2 to 3 m; bronze new growth

Others worth considering...

  • Acmena smithii "Minipilly" - 2 m
  • Austromyrtus inophloia " Blushing Beauty" - 1 to 1.5 m; Pink/purple new growth
  • Callistemon salignus "Great Balls of Fire" - 1.75 m; red new growth
  • Callistemon "Captain Cook"
  • Leptospermum petersonii (Lemon-scented tea tree)
Callistemon "Captain Cook".

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How Plants Make Food

Hi, my name is Daniel Stubbs and I live in Beauty Point Tasmania, which is located in the Tamar Valley North of Launceston.

My class 4 is studying plants at the moment and my project requires me to know about how plants make food.

Can you please assist me with an answer or direct me to a web site where I may find more information.

Thank you for your help

Daniel Stubbs

This is a good question and I was sure that there would be something useful on the web. After a bit of searching I came up with the following site which should answer your questions:


The Online Biology Book (reviewed in Issue 13 of Australian Plants online) is also an excellent reference although a bit too advanced for your present needs. You could also trying searching the web using "photosynthesis" as a keyword.

I hope this helps and good luck with your project.

A Sad Native Pepper


I brought my pepper leaf plant down to Melbourne from Renmark. It started to leap out of its pot, in its shaded position under another tree. Now the leaves are dropping off. This occurred rather suddenly....during the extremely hot weather it was fine and dandy.

The leaf drop is unusual in that they are going brown only half way up the leaf. They literally dry and snap off.

I have tried repotting and "Osmocoting" and have placed the pot in a deeper bed of mulch to see if that helps. I have started waving a watering can over it more frequently but worry that that will make it too wet.

I am rather new to gardening these plants in particular. It is complicated by the fact that at the moment all my plants are in pots. Any thoughts or is it doomed?

Sandra Kingston
Box Hill, Victoria

John Wrigley replies.....

I am not sure what species you are growing. Is it a Tasmannia sp.? If so, there are several species, all of which are rainforest plants, some coming from lowland rainforest and others from higher altitudes in the Dorrigo and Barrington Tops areas of NSW. There is also a tropical species.

They are relatively easy to grow but require shade and regular watering. They also respond to some general fertiliser application. You do not say in what size pot you are growing this plant. Could it be root bound and suffering from water stress? I suggest that the leaf drop may be a result of the hot weather.

Your plant would probably be better in the ground if you have a suitable coolish site. In the meantime, I suggest that you cut it back a little and keep it moist.

Good Luck

Defining "small"

I note your recipe for a suggested potting mix for Aussie Native Plants. I wonder if you could quantify the recommended "small" amount of slow release fertiliser mentioned in your web page. I realise that it should be a fertiliser for natives.

I've been looking for a precise figure without success.

Could you provide an amount per 10 lt bucket of mix, for example?

Peter Stuart

Seems like a simple question..I'm not sure there is a simple answer.

Firstly the term "native' is misleading...there are lots of native plants and some respond well to fertilizer just like any exotic plant. These are generally the plants that are found in rainforests on rich soils. So you can fertilise these fairly regularly with a general fertiliser.

Other plants are native to nutrient deficient soils and these are the ones that the "native" fertilisers are designed for. These can often be sensitive to excess phosphorus which is why so-called "native" fertilisers usually have a lower phosphorus content than most general fertilisers. Even among this group some are more phosphorus tolerant than others. The ones where care is needed is often with plants in the "Protea" family such as Banksia, Grevillea, waratah etc.

As for a precise figure...I can't give you one. You can fairly safely apply "native" fertilisers at the rate mentioned on the packaging but I'd reduce the dose by at least half for phosphorus sensitive species (you can see a list of these in the article "Phosphorus Needs of Australian Plants" in the December 1997 issue of Australian Plants online - available in the Back Issues section of the current issue of APOL.

This is probably not quite the answer you wanted but it's the best I can do...there just isn't a magic number when it comes to fertilising. My motto is "Is in doubt, don't fertilise at all".

Eucalypts from Cuttings

I am a third year student of Charles Sturt University doing a Bachelor of Applied Science, Parks, Recreation and Heritage and studying horticulture as my minor. As part of the subject, Plant Propagation, I am required to research propagation techniques of a species including seed, cuttings, grafting / budding and tissue culture.


My special interest is with natives and I chose Corymbia ficifolia. I have many books and literature on propagation via seeds and grafting but I am having difficulty on cutting techniques and tissue culture. Although I understand that propagating all eucalypts from cuttings is usually difficult and unsuccessful, I am interested in the actual method of attempting to propagate Corymbia ficifolia via cuttings.

Also, I am interested if tissue culture is used and what method is adopted.

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I would appreciate any help in sourcing this information and any useful comments or assistance, especially any internet or library references from you would be very much appreciated.

Linda Murray
Albury, New South Wales

John Wrigley replies....

Eucalypt propagation from cuttings is, as you say, very difficult and the only success that I am aware of is using juvenile foliage. For many species, including Corymbia ficifolia, cuttings may be struck using seedling material with up to six pairs of leaves. Some work was done in this field by Rudolph Willing in the 1970's at the Botany Dept of the ANU in Canberra. Rudolph retired many years ago as a Technical Officer with the department and I have no idea whether his records are still available.

I do not know of anyone using tissue culture as a method of propagation of eucalypts but an enquiry to Iain Dawson at the Australian National Botanic Gardens, Canberra would be worthwhile.

Wattles at the Winery

Wine Bottle

A fellow Uni. student has a vineyard at Mudgee and wants to plant Australian native plants along the road boundary. Suggested to him (from another source) were Cootamundra wattle and an unknown Callistemon. I was concerned about Cootamundra wattle because of its ease to self seed but also suggested Callistemon viminalis because of its lovely weeping habit. Would you, or others, know what plants are suitable for the Mudgee area?

The question was also raised as to whether the birds attracted by the natives would also be attracted to the grapes on the vines? Any answers would be most welcome. :-)

Merilyn Mosher

The wattle may not be a problem there...it's mainly of concern when planted near natural bushland.

If you plant things like callistemons, banksias, grevilleas etc I don't think the birds would be a problem as the plants attract nectar feeders rather than fruit eaters. Avoid species which develop berries etc such as lilly pillys and many rainforest plants.

I'm not really qualified to comment on suitable plants for that area but the Society has a Central West group which covers the Bathurst - Mudgee - Dubbo area and I'm sure they could help. They also have a web site which should provide contact info.


I am studying Natural Resource Management at the Adelaide Uni.


I am looking for information about Hardenbergia violacea for a species study I am currently doing. I would be grateful for any information you may be able to send me about the history of the plant (who discovered it,etc) the climate were it grows and other information you think is relevant, as I've had trouble finding the information I need about this plant in books and on the internet.

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for a higher resolution image (35k).

Some specific questions are:

  1. Was Hardenbergia violacea used for food or medicinal purposes by the Aboriginals?
  2. Do animals or birds use it as a food source?
  3. Is it used for anything today such as in gardens or in floral arrangements?
  4. How is it pollinated? (wind, insects, birds)
  5. Has it got any special adaptations that help it survive in the Australian environment and why are they needed? (fire resistant, flooding needed for life cycle eg. river red gum)

Nathan Smith

There is some information on the plant, including its natural distribution, naming, cultivation, etc, on our web site.

As to your specific questions.....

1. Not as far as I know....none of my references indicate any real use by Aboriginal people. According to Tim Low ("Bush Medicine") , the roots of the plant were used by early settlers as a substitute for sarsaparilla.

2. Again, not as far as I know. Insects probably attack the young seed pods for food.

3. It's widely used as a garden plant by native plant enthusiasts and it is also commonly available in general garden centres. I know of no use as a cut flower (at least commercially) - the flowers probably don't last well once cut.

4. I believe it is mainly insect pollinated but wind may also help. Birds don't seem to be a factor.

5. Most pea flowered plants are "pioneer species" after a bush fire in that they grow quickly to stabilise the soil while longer lived species (eg eucalypts) get established. They have hard seeds which need the heat from a fire to crack the seed case and allow germination to proceed. They also have root nodules which can "fix" (take up) nitrogen from the air. This nitrogen gets incorporated into the soil when the plants die.

Dying (not dyeing!) grevilleas....again

Sarah Santitoro's plea for help with her yellowing grevilleas (Electronic Mailbox, March 1999) brought the following help from fellow Californian resident, Andrew Wilson....

Sarah asked why her Grevilleas were getting yellow leaves and dying. There are many possible answers, as suggested both in her question as well as in your reply. Your answer about soil richness may turn out to be the right one but, if not, here is another idea. Simi Valley can get cold in winter. What was the minimum temperature there this winter?

If it was not below 25F (-4C) I suspect the problem may be soil alkalinity. Soils are often alkaline in this part of the world and the water does not help. In my experience the best way to get rid of yellowing leaves but not the plant itself is to apply a heavy dose of sulphur. Flowers of sulphur or agricultural sulphur applied heavily around the base of the plant once every two months until you see improvement will help. It will serve to release missing nutrients that a number of the protea family members need - iron and magnesium. No guarantee this will work as I've not seen the soil. But, it may help if the soil tests show the soil is alkaline.

Some grevilleas are less demanding of acid soil than others but that is a long story.

Dyeing (not dying)

I am currently involved with a school project. I must find out some native Australian Plants, that I can dye cotton with (the colour). I have had a lot of trouble trying to find some information on this subject and I was wondering if you would please be able to help me?

Talia Campbell

There's not a lot of info available to my knowledge but there is an article called "Dyeing with Eucalypts" which is on our web site.

The article is concerned with dying wool rather than cotton but it may be worth looking at.

There is also a publication called "Dymaking with Eucalypts" by Jean K Carmen. I haven't seen this and I don't know how easy it would be to obtain but perhaps your local library could get a copy on inter-library loan.

Concerned about Cold

I have been growing (on an experimental basis) four specimens of the stiff bottlebrush (Callistemon rigidus). Two of these specimens have withstood three of our winters (the remaining two being planted somewhat later). They grow quite well and aggressively (so far). As expected, they handle drought, heat, and general neglect very well.

Do you have any detailed information as to how cold a temperature they can withstand? I would not have expected this plant to survive in this climate, but so far they have been exposed to 14 deg. F (or -10 deg. C). At what temperature should I start being concerned?

Allen Waters
Virginia Beach, Vermont, USA

To be perfectly honest....I haven't got a clue!

In its natural habitat, C.rigidus would experience temperatures to around -5 to -10 C occasionally in severe winters but not on a regular basis. Just how much below -10 it could tolerate is something we have no experience of here. I would certainly be interested in your experience in growing this and other Australian plants in your climate. We often get questions regarding cold tolerance that are impossible to answer at present.

Syzygium Roots

I am an amateur gardener, and I like Syzygium paniculatum very much. I like its form and I like its vigour, however I have been warned that its roots can be a problem. Are the roots of this plant invasive?

Do they tend to surface? If you intended to allow the tree to grow to an uncontrolled height, would you plant it two meters from a concrete foundation? How close would you in good conscience get?

I would be grateful for any information you can provide.

Dan Connally
Sant Barbara, California, USA

Jeff Howes replies.....

Not an easy one to answer from Sydney Australia and as well I am not too familiar with the your climate. . What I will do is to give you some facts about its growth in Australia and you should be able to draw your own conclusions ( I hope).

Syzygium paniculatum is a tree to 8 metres (26 feet) with a dense bushy crown and prefers not to grow in hot humid climates. It is easy to grow and will tolerate full sun and flowers in summer. It has been widely cultivated for over 50 years and prefers sandy soils and coastal areas. They grow in a temperature range of a min 8 degrees C to a max of 32 - 34 degrees C. That is, on the coastal strip, just below Sydney NSW to just below the Queensland border.

To my knowledge, it does not have a reputation for invasive roots although if moisture is present (eg leaky pipes) it will certainly be attracted to that (as most trees are).

As for planting it 2m from concrete foundations - I think that is a bit close if it grows to 8m. Are there any other Syzygium paniculatum growing in your area, if so how high do they grow? In sunny California they may even grow more than 8m.

Hope this is of some help?

Lechenaultia from Seed


Greetings from Indiana! I would like to ask for suggestions as to how I might achieve success in germinating Lechenaultia biloba seeds. I gather this is not the preferred means of propagation, but I've got a gram of the seeds and I want to give it a go. Would presoaking help? Any tips would be greatly appreciated!

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for a higher resolution image (35k).

Larry Laffrey
Indiana, USA

I don't know that I can be much help. As you indicate, seed is not the preferred method of germination - they strike easily from cuttings. There are no special "tricks"....unfortunately the seed can germinate well sometimes and not at all at other times.

I can only suggest that you sow the seed in a good seed raising mix, cover lightly, keep moist and hope for the best!

Who was Joseph Banks?

Do you know who Joseph Banks is and how he relates to plants? If so would you be able to tell me a bit about him?

Rachael Howsam

My pleasure....

Sir Joseph Banks was the botanist on Capt James Cook's voyage to the South Pacific on which they were the first Europeans to discover the east coats of Australia in 1770.

Banks (and his colleague Daniel Solander) collected many plants south of where Sydney is now located and it was these discoveries that caused Cook to name the place Botany Bay.

If you want to find out more, take a look at the Joseph Banks Papers web site.

Pruning and germinating waratahs

I have a three year old "NSW Waratah" which has flowered each year. It has started to become "leggy", but, as it is in bud, I don't want to prune it just yet. After flowering I would like to know how I should prune it to get a bushier plant.

My second question is that this plant produced a seed pod from last year's flowering. I have harvested the seeds by removing the pod just as it opened and letting it dry in a brown paper bag. Do you have any suggestions about propagating these seeds?

Stephen Miller
Alfords Point, New South Wales

Jeff Howes replies.....


  1. Extract from a handout (late 1980's I think) of an article produced by Sydney Uni titled 'The Waratah from Seed to Flower'
  2. Dept of Agriculture Bulletin P52 'Growing Waratahs' dated 1972.


For the first five years cut to 25 cms of last year's growth. After five years cut back to 10 cm of last years growth until tree is 2.5 m high. If trees get scrappy and stems too short, the flowers may be left for seed prior to a severe rejuvenating pruning. Trees which have been left to develop without sufficient control should be treated similarly. This entails cutting the plant back to 70 cm of trunk or growth. Preferably in early Spring. Failure to prune will result in a tall spindly plant with few flowers.


Start with fresh seed, usually harvested and cleaned late autumn to early winter. Allow pods to open in a dry warm place. Do not use seed older than six months, unless specially stored at low humidity and low temperatures. In August, sow in coarse sand or well drained soil in a container with drain holes. Cover with a few millimetres of soil. Drench with a soil fungicide at recommended rate and keep in a warm light place. Seedlings should emerge in one to two weeks (the Dept of Agriculture advises three to four weeks). I tend to agree with the shorter estimate.

Native Lawn Grasses

Are there any Australian native grasses that are suitable for lawns? If so where can I obtain them?

Trevor Smallwood
Canberra, ACT

Not as far as I know - at least not for a regularly mown traditional lawn.

You might like to contact AABULK, 11 Ingolds Lane, Clarendon, NSW, 2756. (02 4577 5912). They are growing a range of native grasses and may be able to provide further info.

If any readers have some advice on this, perhaps they could let Trevor (and me) know.

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Australian Plants online - June 1999
Association of Societies for Growing Australian Plants