Australian Native Trees and Tall Shrubs For Dry Areas
This is the first list of plants for dry and alkaline soils. They need to be watered regularly for the first few months at least.
- Acacia pycnantha (Golden Wattle) Australia’s floral emblem. 4-8m high in ideal conditions.
- Acacia saligna (Golden Wreath Wattle) 3-8m high.
- Acacia baileyana (Cootamundra Wattle) to 6m. Amazingly, this does well here.
- Eucalyptus leucoxylon forms
- Eucalyptus diversifolia
- Eucalyptus porosa
- Eucalyptus stricklandii
- Eucalyptus spathulata
- Eucalyptus woodwardii
- Eucalyptus torquata (Coral Gum)
- Eucalyptus platypus
- Eucalyptus macrocarpa (Rose of the West or Mottlecah)
- Eucalyptus ficifolia (Western Australian Flowering Gum)
- Eucalyptus erythrocorys (Red Cap Gum)
- Eucalyptus eremophila
- Eucalyptus forrestiana (Fuschia Gum)
- Eucalyptus pyriformis (Pear Gum)
- Eucalyptus sideroxylon (Iron Bark)
- Grevillea robusta
- Santalum acuminatum (Wild Peach, Quandong)
This is not an exhaustive list. If you know of more species to add to this list (ie. dryland planting plus alkaline soil), let me know, please.
Planting in Dry and Alkaline Areas
I have been finding plants in the nursery that need to be planted out while the soil is still reasonably warm. There are quite a few, including some very neglected Eucalypts. Thought I would do a list in the blog of plants for our dry situation here. The average rainfall here is 330mm or 13 1/4 inches. Mostly winter falls, and often not heavy at any one time. When we get more than 20 points (5mm) in a day it is a time for rejoicing. We had 40 points last Thursday and the benefit can be seen immediately.
The soil here is mostly very alkaline. Some areas of the town and outlying districts go down to neutral. The soil structure is quite good apart from patches of ‘non wetting’ or water repellant sand. It is the limestone rubble that is the problem. At least the drainage is good. None of the books will say what plants will adapt to these highly alkaline soil conditions. In fact there are many plants which will grow happily in alkaline soil, even though the books do not say this. It is the highly alkaline soil which makes life a little more difficult. It has to be a trial and error situation. So my list will reflect what I know to be true.
It is worth getting the soil tested. A test kit costs something like $25 and will last for years. If there is an opportunity to have soil tested at a plant sale, take advantage of the offer. Sometimes plants which are acid soil lovers will grow in alkaline soil, even if not to the ultimate size that is listed. Others will look very yellow and deteriorate. There are remedies which will improve this, like iron chelates or sulphur watered in to the soil surrounding the plant. Follow the directions on the container.
In poorly drained soil it is worth raising the level of the soil by creating small catchment areas and adding the soil to one side in the form of a mound. Planting on the mound will make an amazing difference to some plants. I have heard that the raised area will also decrease the effects that high alkalinity has on some plants.
I will begin the list tomorrow.
Grevillea in the USA
I was looking at blogs to do with gardening last night and came across a site called the Golden Gecko written in California (the name attracted me). That’s not too amazing in itself. What hit me in the face were the photos of Grevillea ‘Molongolo’ and Grevillea lavandulacea ‘Penola’.
These were being recommended as suitable plants for the impoverished soils in the area. And they would be good for that purpose. They also do well here (country South Australia).
“Molongolo” is a registered cultivar, a hybrid between a dwarf, yellow form of Grevillea juniperina from New South Wales and an upright, red-flowered form of G juniperina from near Canberra, ACT. It can grow up to 5m across in ideal conditions (I’d like to see that here!), with apricot coloured flowers. It needs to be tip pruned from an early age to encourage the denseness of a good ground covering plant. It also responds well to pruning.
As with most plants, pruning is best done after flowering but this plant has a long flowering period. In general I would say that when there are signs of new growth is a safe time to prune most evergreen plants. As a rule don’t prune back to bare wood, but look for small branches or shoots to cut back to (unless you know for sure that the plant will shoot from bare wood).
Grevillea lavandulacea ‘Penola’ has been in cultivation for many years. It has greyish foliage with a massed display of red and cream flowers which look wonderful against the grey foliage. Apparently there is a question about whether it is actually a true form of G lavandulacea as it is very close to Grevillea ‘Poorinda Illumina’. We’ll let the botanists fight about that! The town of Penola is in the south east of South Australia.
Daisy Seeds
I own my own small scale nursery and there always seems to be too much to do. I decided that I had had enough one day and thought I would just propagate for myself. Trouble is I can’t walk past a plant with cutting material on it and one packet of seed provides many more plants than I can use. I propagate for the major Plant Sales organised by the Australian Plant Society in Adelaide, and the occasional country market.
Hence the mad flurry of activity at the moment. No cuttings and seed in means no plants later. You cannot decide to go to a sale and not have worked months before to have the plants available. Raising seed is quite successful at this time of the year.
So I was really pleased to see that the seed of two Olearias (daisies) have begun to germinate. One that I prize greatly is a lovely mauve daisy, Olearia ciliata native to the mallee areas and in particular this seed came from Eyre Peninsular, SA. It has germinated within 2 weeks of sowing and I used Regen smoked vermiculite sprinkled over the seed.
There is some evidence that natural rainfall will stimulate germination in native daisies, particularly Brachyscomes. Our recent rains may have helped in this case, but whatever, I am pleased to see it.
Work, Work and More Work
No Comments »27th March, 2006; Category: General
We had about an inch (25mm) of rain overnight and more today. That’s a thirteenth of the year’s average. Having it fall in such a short period of time is wonderful as it soaks down deep. With mild weather this week I’m torn between potting on cuttings and seedlings, putting in more cuttings and seed and getting out with the mattock and digging holes for plants while the soil is soft and there is moisture to kick them along. I hate having to choose when all are so important in the life of the nursery.
I have taken the opportunity today to be inside putting in more cuttings. The packets of seed have their hands up too! So we just plod along getting as much done as possible and hopefully getting to the end of the main activity soon.
Then I might get on with the rest of the gardening, pruning, maintenance, repairs to the nursery, setting up new growing on areas, getting rid of weeds, making some paths, cleaning pots, setting up irrigation, finish tiling inside, make new curtains, painting inside and out, and with a bit of luck sewing and craft!!
I don’t want much.