Kitchen garden subtropical
Arno is a garden designer and writer whose garden in Brisbane is mostly edible.
He is constantly testing the received garden wisdom for its relevance to subtropical gardeners, and trialing new products. Let's see what Arno's growing this spring
As the cool climate veg are cleared out of beds, consider installing an automatic drip irrigation system. Not only will you conserve water, but you can relieve yourself of one of the most tedious and time-consuming garden tasks, and feel free to go on holiday with a clear conscience. Modern systems are more sophisticated, cost-effective and easier to install than those of the past. Battery-operated controllers are simply attached to the tap. Drip tubing provides consistent water levels across the system. The irrigation manufacturers provide instructions online about what you need and how it to put it together, and if you don’t fancy DIY, commission a company to install the system for you.
In central and northern parts of Australia, spring is generally dry and increasingly hot, with the burning sun in a cloudless sky. Cool-climate vegetables react to these conditions by bolting or producing leaves that are coarse and bitter, signalling time to clear beds and replant with warm-climate crops.
Time to clear the beds.
Leafy vegetables that are tolerant of the increasingly hot, dry and sunny conditions are my go-to choices for spring greens. Wild rocket is a year-round staple - remove the flower stems as they appear to encourage leaf production. If you enjoy cabbages, try growing collards, African cabbages (Ethiopian and Kenyan varieties), Couve Trochuda (Portuguese or Brazilian Kale) and kailan (also sold as Hong Kong broccoli). Mustard greens also thrive. These vary from fiery broad-leaved cultivars, suited to stews and soups, to mild, fine, frilly-leaved cultivars, which are delicious in salads. Sow seeds directly in drills and cover initially with shadecloth.
Best known for its delicious and iconic jam, the ‘fruit’ of rosella (technically fleshy calyxes rather than actual fruits) are wonderful additions to a wide range of savoury and sweet dishes. I’m a great fan of the cranberry-flavoured young leaves, which I add to salads or lightly stir-fry, while the dried ‘fruits’ make a delicious hibiscus tea. Plant seedlings 700mm to 1m apart as soon as the ground warms. Provide regular water and fertiliser for strong growth. Lightly prune back bushes a couple of times before Christmas. The shortening days after Christmas encourage the plant to produce flowers and ‘fruit’ rather than leaves.
Okra is one of the easiest vegetables to grow and one of my favourites. It is pest and disease free and will thrive and produce heavy crops until early winter. Sow seeds directly once the soil warms (for me, that's the end of September, when the coconut oil in the pantry cupboard starts to soften). Sow on a 500 to 900mm grid, with two seeds per hole. Once plants are 300mm high, remove the weakest plant. The attractive hibiscus-like flowers are followed by tender pods. Pick pods while young as some varieties have pods that become fibrous with age.