AUSTRALIAN NATIVES I

Australian Plants Course

They are grown commercially as cut flowers in Israel and South America. Eucalypts are widely planted trees throughout California, and increasingly popular in places from Southern England to the middle east. Macadamia nuts and Tea Tree Oil are produced in commercial plantations not only in Australia, and beyond. Many Australian natives are also well suited as indoor plants.

Australian climatic conditions range from hot-dry to cold-wet; soils also vary according to region from alkaline to acidic. Consequently the plant life of this large country is abundant and diverse, offering an interesting range of possibilities, whether you live in Australia or elsewhere.

COURSE AIM

Develop an ability to identify, select, cultivate and plan a management program, for appropriate varieties of Australian native plants, in a wide variety of situations.

Start with this introduction to Myrtaceae Plants - many of which are Australian natives

WHAT'S SO GOOD ABOUT NATIVES?

There are a number of reasons why Australian natives are worth growing. There is an enormous variety of Australian native plants – at least 20,000 species, including around 700 species of Acacias and over 500 species of Eucalypts. One can find native plants for just about any situation, from deserts to rain forests to alpine regions. Many natives have evolved to withstand harsh conditions: there are species tolerant of saline conditions, arid conditions, strong winds, pollution, and flooding. It is important to remember that the natives that come from your own area have evolved to cope and thrive under those local conditions.

Many Australian natives have extremely attractive flowers, fruit, foliage or habit, some unlike anything found elsewhere. In fact, a large number of indigenous Australian plants are endemic that is, they do not occur anywhere else in the world. By growing natives, we can help ensure that these species are preserved. Also, the flora and fauna of Australia have evolved together over long periods of time, so by growing Australian natives we can encourage the survival of native fauna.

While some have been widely cultivated, many Australian native plants are new to the world of gardening, some so new that we are still learning how to grow them properly. Unlike plants from some other countries, relatively few Australian plant species have undergone extensive plant breeding or plant selection programs. We are still often working with raw material from the bush whereas plants such as camellias and roses have been grown, hybridised and generally studied for hundreds of years. As yet, many horticulturally valuable species still haven't even been collected from the wild. Some notable exceptions such as the Kangaroo Paws (Anigozanthos sp.) and the Geraldton Wax (Chamelaucium sp.) have been the focus of breeding and selection programs over the last few years.

Lesson Structure

There are 9 lessons in this course:

1. Introduction
   • Scope and Nature of Native Plants
   • Taxonomy: Botanical and Horticultural Nomenclature
   • Binomial System
   • Levels of Division
   • Plant Families
   • Species, Hybrids, Varieties and Cultivars
   • Botanical Keys and their Use
   • Origins of Australian Plants
   • Continental Drift
   • Resources for More Information
   • Sources for Seed Information
2. Cultural Techniques
   • Cultivation
   • Pests, Diseases, Environmental Problems, Nutrition
   • Soils
   • Improving Soil Structure
   • Soil Water Management
   • Compost
   • No Dig Growing Techniques
   • Feeding Natives
   • Pruning
   • Temperature
   • Planting, Staking, Mulching
   • Special Planting Techniques
   • Natives for Shade
   • Controlling Weeds
   • Propagation; seed, cuttings, etc
   • Stock Plants
3. Eucalypts
   • Introduction
   • Types of Eucalypts; gums, stringybarks, boxes, ironbarks, yates, peppermints, etc.
   • Hybrid Eucalypts
   • Eucalypt Cultural Requirements
   • Review of Important Eucalypt Species
4. Native Trees
   • Casuarina; Casuarina and Allocasuarina, Gymnostoma and Ceuthostoma
   • Casuarina Culture
   • Review of Casuarina and Allocasuarina species
   • Australian Conifers: Overview
   • Cupressaceae: Actinostrobus, Calitris, Diselma
   • Araucariaceae; Araucaria
   • Podocarpaceae; Dacrydium, Microcachrys, Microstrobos, Phyllocladus, Podocarpus
   • Taxodiaceae:
   • Macadamias
   • Brachychiton
   • Angophora
   • Lophostemon
5. Acacias
   • Introduction to Legumes; Papilionoideae, Caesalpiniodeae and Mimosoideae
   • Overview of Acacia
   • Acacia Cultural Requirements
   • Review of Important Acacia species
   • Elements of drawing a Landscape Plan
   • Landscape Design Procedure
6. Myrtaceous Australian Plants
   • Review of the Myrtaceae Family
   • Callistemon overview
   • Callistemon Culture
   • Important Callistemon cultivars and species
   • Leptospermum overview and Culture
   • Important Leptospermum Species
   • Baeckea
   • Calothamnus
   • Calytrix
   • Eugenia
   • Homoranthus
   • Kunzea
   • Melaleuca
   • Micromyrtus
   • Scholtzia
   • Syzygium
   • Verticordia
   • Thryptomene
7. Grevilleas
   • Grevillea Overview
   • Types of flower: Erect Cluster, Toothbrush, Pendant, Cylinder
   • McCilveray’s Classification into eleven main groups
   • Flower and Leaf Terminology
   • Review of Low Growing Grevilleas
   • Banksia Type Hybrids
   • Hybrid Parents from tropics and sub tropics
   • Poorinda Hybrids
   • Review of many Important Species
   • Culture
   • Related Proteaceae Natives: Dryandra, Hakea, Banksia, Telopea
8. Ground Cover and Small Shrubs
   • Overview of Fabaceae (Egg and Bacon) Plants
   • Brachyzema
   • Castenospermum
   • Clianthus
   • Gastrolobium
   • Gompholobium
   • Goodenia
   • Hardenbergia
   • Hovea
   • Jacksonia
   • Kennedya
   • Oxylobium
   • Swainsonia
   • Viminaria
   • Boronia; overview and culture
   • Boronia species
   • Prostanthera
9. Commercial Applications
   • Fragrant Natives
   • Uses for Eucalyptus
   • Uses for Grevilleas
   • Uses for Acacia: timber, tanning, cut flowers, food, etc
   • Aboriginal Uses for Acacias
   • Growing Natives in Containers
   • Bush Tucker

Aims

• Classify most significant cultivated native plants, to the family level.
• Determine cultural practices to maintain healthy native plants.
• Explain the identification and culture of eucalypts in your locality.
• Explain the identification and culture of native trees.
• Explain the identification and culture of acacias in your locality.
• Explain the identification and culture of native shrubs, including species of Acacia, Melaleuca, Callistemon and Leptospermum.
• Explain the identification and culture of different Proteaceous native plants, with particular emphasis on the genus Grevillea.
• Explain the identification and culture of a range of Australian Native ground covers and small shrubs.
• Determine commercially viable applications for different native plants.

COMMONLY GROWN NATIVE PLANT FAMILIES

 
Myrtaceae
The Myrtaceae family contains some of the most significant Australian native plant genera, including Eucalyptus, Corymbia, Callistemon, Melaleuca, Lophostemon, Thryptomene, Angophora, Agonis, Baeckea, Leptospermum, Eugenia, Astartea and Micromyrtus. Non-native genera in this family include Myrtus (Myrtle) and Feijoa. Members of this family are generally hardy and adaptable to a wide range of conditions. Most can be readily propagated from seed, and many of the smaller shrub types are often also propagated by cuttings.
 
PEA FAMILIES

The following three families were formerly included as subfamilies in the Leguminosae (the ‘Pea’ family). They are now recognised as three separate families:

Mimosaceae
Flowers appear like a fluffy ball or cylinder (stamens are large and much more obvious than petals), and seeds develop in pods. Mimosaceae includes the genera Acacia, Albizzia and Nepuntia.
 
Fabaceae (syn. Papilionaceae)
These have a typical pea-like flower (there are five petals, two are joined and three are free), and seeds develop in pods. Fabaceae includes the genera Aotus, Oxylobium, Pultenaea, Hardenbergia, Kennedia, Gompholobium and Swainsonia.
 
Caesalpinaceae
These plants have five petals, all obvious and free (not joined). Flowers are asymmetrical, and leaves are normally compound. This family includes the native Cassia and non-Australian plants such as Bauhinia and Gleditsia.
 
All leguminous plants are characterised by their pod-type fruit. They are also useful for improving soil fertility colonies of bacteria on the roots convert nitrogen from the air to feed the plant. Most native legume species are propagated from seed which is first soaked in boiling water.
 
Proteaceae
A diverse family with around 800 species and 38 genera in Australia. They are commonly known for the large, showy flowers which are borne on many species. Examples of Australian native genera in this family include Grevillea, Banksia, Hakea, Stenocarpus, Isopogon, Telopea, and Dryandra. Flowers are variable, although the petals tend to be insignificant. Leaves are often thick and dry in texture, and often with sharp tips. Seeds are large and woody.
 
Generally plants in this family require well-drained soils and commonly suffer from iron deficiency and phosphorus toxicity in cultivation. Some rainforest genera, including Macadamia, are an exception. They require more phosphorus than other genera in the family. Root rot is also a common problem. Propagation is commonly from seed for most species, with the exception of notable exception of grevilleas, which are grown from cuttings. Many species from other genera have, however, been successfully grown by cuttings or grafting.

Rutaceae
Twenty genera in Australia including Asterolasia, Boronia, Correa, Crowea, Diplolaena, Eriostemon, Flindersia, Geijera, Microcitrus, Murraya, Phelabalium and Zieria. Leaves of species from this family are covered with small dots (oil glands); flowers have either four or five petals. This family includes many small shrubs with attractive flowers.
 
Pittosporaceae
Most of the plants in this family are native to Australia. Notable genera include Pittosporum, Hymenosporum, Bursaria, Billardiera and Marianthus. Flowers have five petals, leaves are simple (undivided) and arranged alternatively on the stem, and fruits are either a berry or capsule (often attractive). Many varieties may be propagated from both seed and cuttings.
 
Asteraceae (Compositae)
The daisy family has a worldwide distribution of about 800 genera and 12,000 species. Australian genera include Helichrysum, Bracteantha, Olearia, Rhodanthe and Brachyscome. The flowers are actually a composite of many small flowers fused together to appear as one single flower. If the flower is pulled apart it can be seen that it is made up of many individual units, each one having its own set of floral parts (petal, stamen, stigma, ovary, etc). Some Asteraceae flowers are incomplete and have only some of the floral parts. Flowers in this family are generally fast growing, flower prolifically, and prefer well drained soils. Many are excellent cut flowers or are used for dried floral arrangements.
 
Lamiaceae (Labiatae)
Commonly known as the mint family, genera in Australia include Prostanthera, Westringia and Hemiandra. The stems are roughly four-sided (similar to a square or rectangle in cross-section). The leaves are simple (not divided like a pinnate leaf), and are arranged in whorls around the stem. The flowers are two lipped. Members of this family can often be identified by their pungent smell when the leaves are crushed. Most are relatively hardy and tolerate damp soils at least for a short period.
 
Epacridaceae
Heath-like shrubs including Epacris, Leucopogon, Sprengelia, Styphelia and Richea. Flowers normally have five petals which are joined in the lower part of the flower to form a tube. Leaves are generally fine, stiff and often prickly. Most species have fine roots that are easily damaged if the soil around them is disturbed (i.e. cultivated). Most prefer moist but well-drained soil.
 
Orchidaceae
There are around 15,000 species of orchids distributed worldwide, with 551 species in 91 genera in Australia. Most are found in the northern rainforests, although some extend into colder temperate regions. The majority of those found in the southern parts of Australia are terrestrial (growing in the ground), while many of those from subtropical and tropical areas (eg. Dendrobium) are epiphytic (growing on tree trunks, rocks and fallen logs). Flowers are complex, and often very showy. Five petals make up an irregular-shaped flower. The stamens unite with the pistil to form a structure called the column. All species are perennial and have thickened tuberous or bulbous roots.

Orchids are mainly propagated by division or tissue culture. Many of the showier tropical species have been widely hybridised, and many cultivars are known.
 
Liliaceae
The lily family includes some 2000 species worldwide, many of which are bulbs cultivated for ornamental purposes. The flowers have six petals, usually separate, but sometimes fused. The ovary is superior (ie. sits above the point where you find the base of the petals). Some Australia members of the Liliaceae are found in the genera Asparagus, Bulbine, Blandfordia, Dianella and Thysanotus. These are commonly found in heathlands and drier forests of south-east Australia. Exotic examples include onions (Allium), tulip, hyacinth, lilies and aloe.