Five years of funding totalling $128,000 from the Australian Government Biodiversity Fund has seen Goondiwindi Botanic Gardens “come of age”.
Over 2,000 new plants have gone in, with a concentration on the mid and under storey and groundcovers. This was made possible by the maturing of the over storey plantings, first commenced in 1988. Kevin Sloan and Di Sheinberg have done all the on ground work, a massive effort. Before plants can go in the ground the sites have to be prepared by ripping, mounding, hole digging and weedmat installation. A slow release fertiliser tablet is placed in the hole, followed by setting the plant and filling around it. A tree guard is put in place, mulch is applied, and a dripper connected to the automatic watering system is installed. This attention to detail has seen an excellent survival rate over the years.
A magnificent Chinchilla White Gum
Another great boost from the Biodiversity Fund was the construction of our state-of-the-art propagation facility in the compound. The heater-mister unit, glasshouse and shadehouse all have automated sprinkling and misting systems which provide the necessary climate control. Kevin and others have put together a growing seed collection from the Gardens and elsewhere. Cuttings are freely available. We are now able to produce many of the plants we need to increase planting densities and replace short-lived species.
Healthy plants in the shadehouse
Because of the capacity we have developed a keen propagation group has started up with an initial 20 members. Bernadine Paesler has shown us how to strike soft woody cuttings, and we expect to become very productive at and between our monthly Sunday morning sessions. New members are welcome at any time.
Some of the 20 members of the propagation group
The plants we grow will be for the Gardens but also for street and park plantings, restoration of riparian zones, and use by landholders in projects such as shade lines and even agri-forestry. When we are fully operational we will be taking orders for job lots.
All in all, the Biodiversity Project has been a great success. The Gardens are years ahead of where they would be without it. We are immensely proud of this magnificent community asset.
Rip or cultivate the soil or maybe top with decomposed granite. Raise the beds if necessary. Add mushroom compost, if not Proteaceae or Australian pea species. Homoranthus and acacias appear to be better off without mushroom compost. Particularly correas and eremophilas love mushroom compost.
Add Plurasil (diatomite)- Martin L’ons 02 67364964 for more information.
Choosing suitable plants
Soil type
For heavy clay soils plant callistemons, melaleucas, westringias, eremophilas, grasses and eucalypts.
For lighter and sandy soils plant grevilleas, pea plants, hakeas, correas and banksias.
Many native plants can be grown successfully if the beds are raised to allow proper drainage to occur.
Foliage contrast is good eg Acacia baileyana purpurea, Acacia fimbriata dwarf & Rhagodia spumescent.
Water requirements
Ground cover grevilleas on the whole are not particularly drought tolerant. Frost hardiness: guards &/or blue metal can help.
Plants should not be pot bound; squeeze the pots to check they are flexible.
Temperature is important to many plants. On the whole, many species of the Myrtaceous family are quite heat resistant. This family includes eucalypts, leptospermums, callistemons and melaleucas. Lilies and grasses are frequently tough in the heat.
The plant family to avoid in hot areas is the Rutaceae family. This includes Correas, Boronias and Croweas. Many grow in granite soils on the tablelands in filtered shade.
Group plants with similar requirements together. Grevilleas and banksias without mushroom compost. Deep-rooting plants and eremophilas where they won’t receive extra water.
Planting
Save your pennies and plant all at once. It is particularly hard to plant later under eucalypts. They take the moisture out of the ground all year round unlike deciduous trees. Plant callistemons, some varieties of melaleucas, lomandras & westringias under established eucalypts – plants need a strong vigorous root system to establish. Grevilleas on the whole are not suitable under eucalypts as they have a limited life span. After they have passed on, it is difficult to grow anything else in their place.
Dig a large hole, add blood and bone and mix with the soil. Blood and bone is useful as it doesn’t turn grevilleas yellow and can be used for all native plants. lt also helps condition the soil and gets the microbes working. Plant also a large rock or log for a cool root run – especially useful for the Rutaceae family. Parts of the garden which only attract morning sun are always at a premium.
Fertilizer tablets can be effective. Agriform tablets last for 2 years. Plant the plant & water in thoroughly – 5 litres. Install a watering system. Mulch the bed – there are a variety of mulches to use. Lucerne hay is excellent for the soil but doesn’t last long. Grass mulch can be practical if baled after the seed has fallen. Weed mat keeps the ground moist but can waterlog plants during wet times.
Rock mulch – try road metal & rout. All the water sinks in, the rock insulates the soil & diminishes frost damage. Guard during winter frosts or heat waves. Milk carton guards with bamboo stakes can be made more effective by pushing loose soil half way up around the outside of the carton. A useful frost guard can be made using a white woven fertiliser bag and 3 stakes to hold it up. lt may be installed with the closed end at the top.
Pruning
When a plant is first in the ground, tip prune frequently or give haircuts. From one year old they may just need one pruning annually so prune during November or after the plant has flowered. Try to encourage shoots from the base. Remove about 1/3 of the plant; any dead limbs, spent flowers or seed heads. This will prolong the life of the plant & stop it from falling over. lt is important not to prune all the small side branches from a tree as this can create an unstable plant.
Deficiencies
The most common deficiency when growing native plants is iron deficiency. The leaves turn yellow around the margins first and finally go black. This is very common with grevilleas and banksias in neutral to alkaline soils. lron chelate is readily available from nurseries. Add 2
teaspoons to a l-litre watering can of water and water around the base of the plant. Rinse off the leaves with clean water afterwards as the iron can burn the foliage.
Set in 25 tranquil hectares on the western outskirts of town, the Goondiwindi Botanic Gardens are a jewel in the crown of rhe region 