SUSTAINABLE does not mean that a garden will endure with no human input.
It means it will survive with whatever limited resources are available and these limits obviously vary from garden to garden, and over time.
So what considerations should we make when planning a garden, particularly in dry times where access to water is limited?
First, think about the size of garden. It must be of a size that enables (not overwhelms) the gardener's ability to tend and nurture it.
Next, financial costs must be within budget. The types of plants you select must be appropriate for the demands of climate, seasons, soils and resources available. Grow more of what does well, give up on those that die.
Don't plan to use pesticides or herbicides. Work with nature, don't kill it.
Inputs of compost, mulch, natural fertilisers must be sufficient for plant needs.
And then there's water. In our drying climate, water is currently our most precious resource. Don't waste a drop.
Local councils provide excellent resources about its wise use. Think carefully about all water usage, and transfer as much water used inside the house out to the thirsty garden.
A garden must also be sustaining. For a lot of us this means plentiful edible plants, herbs and fruits. Composts and mulch reduce water loss, but also sustain vital bacteria, fungi, worms and insects.
Flowering plants are not only attractive to us, but support butterflies, bees, insects, birds. Trees provide cooling shade, habitat for birds and insects, and for some fruit and nuts. Chooks provide fertiliser and wonderful fresh eggs.
For most gardeners the most value comes from time spent in the garden. The mental health benefits of time spent gardening, in contact with nature are well proven.
Science now shows time spent in the natural world releases pleasure hormones oxytocin and serotonin. Our anxieties, stresses and levels of depression melt away.
Think wisely about your garden, love it, and get out into it.