Many resources are available to help you create a native garden. First, it has to be decided on what kind of native garden will suit your situation and whether you want an exotic-native mix or an exclusively native garden. Studley Park gardens range from fully exotic, or a mix of exotic and native plants to fully native gardens.
Indigenous or native
There is another choice which is becoming increasingly popular which is to choose only those plants specifically indigenous to the locality in which they naturally occur. It might be helpful if we restrict use of the term 'indigenous' to the more 'purist' (local only) approach to by-pass confusion. When we refer to native flora, we will be referring to those plants which are indigenous to other suburbs, regions or even states. So be careful about your choice when asking for an indigenous plant; it will be indigenous to somewhere, but not in the way you might have intended!
For simplicity, it's helpful to think of plants outside the immediate environs of Studley Park as natives. Most people are likely to choose a mix, depending on the existing garden, and also depending on the site, orientation to the sun (or shade), soil compatibility, water requirements, drainage issues, not to mention plant shape, height and texture, desired colour and overall aesthetics.
Try to include some locally indigenous plants; the choice ensures an adequate habitat for the birds, animals and insects which have adapted to the plants and helps to retain genetic diversity; you will also be rewarded for your commitment.
Once established, indigenous plants will require less maintenance and watering than exotic species, as they have evolved to adapt to the local climate and soil conditions. It is also worth noting that not all natives will thrive outside their local contexts. One of the best resources for indigenous gardens is the comprehensive Flora of Melbourne (see link below).
While darker soils occur in Kew, particularly close to the river or deeper drainage lines, it is also more likely that you may have lighter grey loam over clay which tends to be moist in winter but is likely to dry out in the upper layers in summer. There is overlap in the soil typology, but whether or not your top-soil is light grey with stony clay subsoil or the darker grey/black grading to pale over mottled clay, it will benefit by the addition of organic matter.
If you decide that native is the way to go, make sure you check with your nursery before deciding to fertilize and if you do need to improve the soil, discuss whether you would benefit from using gypsum if the clay is too heavy. Also, most indigenous plants can be extremely sensitive to lime and also to fertilizers which include high levels of phosphorus. Local plants have a very long history of adaptation to a slightly acidic soil environment. If unsure about the nature of your soil environment or you have problems with certain plants, there are ways of testing and remedying the situation.
What to plant
There are plants for all purposes and situations, no matter which type of garden you choose, including the interesting grasses which have become architectural landscape statements and are becoming increasingly popular, blending particularly well in areas with proximity to the river precinct.
Do check that you avoid environmental weeds. The proximity to the Yarra requires careful consideration to protect the Park and environs from invasive weeds (these can include some natives).
A selection of locally indigenous and some native plants can be found in the stock list of the Victorian Indigenous Nursery Co-operative (VINC) in Fairfield. These plants are mostly sold in tubes, so do not expect large species. However the roots will develop well and growth will be fast. (Large root-bound plants or restricted plants will be harder to establish than smaller species; this is particularly the case for fast growing species which are compromised by too long a life in a pot).
Other nurseries specializing in more broadly native plants (including but not restricted to tubes) include the Kuranga Nursery at Montrose which has an extensive range of Australian native plants. Online and mail-order native plant stock can be found on the Australian Native Plants Society website.
SOME HELPFUL RESOURCES
This Australian Natives Plant Society has a comprehensive gallery, including landscapes for inspiration.
Soil types in Melbourne
Vegetation of Yarra Bend Park (1.3MB PDF, Parks Victoria)
Boroondara Library book links:
Flora of Melbourne, a Guide to the Indigenous Plants of the Greater Melbourne Area: This well illustrated book covers soil types and comprehensive local plant list and information about Melbourne flora, including Studley Park and environs. A list of plants to avoid (environmental weeds) is included.
Grow What Where: This book does what its title suggests, organizing Australia wide plants according to soil types, sun or shade, foliage colour, drought resistance, plants attracting birds to the garden, natives that blend with exotics and many other classifications.
Australian Planting Design: Very good for design including spatial movement; separating space; structures; slopes; suitable (Australia wide) plants.
The New native garden, Designing with Australian Plants: This demonstrates achievable design, for both casual and formal gardens.
http://boroondara.vic.gov.au/freestyler/files/Weeds_Brochure.pdf. For a list of plants
to avoid (some will surprise you!)
Native Plants of Melbourne and adjoining areas. Jones, David & Barbara. Bloomings Books 1999. A convenient little paperback.
Native Trees and Shrubs of South Eastern Australia. Costermans, Leon. Landsdowne 1998. For the seriously interested.