Grow fruit & vegetables in all climates

Story by Hannah Moloney

Here are some tips for growing leafy greens, tomatoes and pumpkin in all climates around Australia.

Leafy greens

Many leafy greens can grow in any of our climates. Check their mature dimensions before deciding where to plant them, as some of the perennials in particular will grow into larger shrubs or vines.

Soil

All greens love fertile, well-drained soil. Prepare soil with compost, well-rotted manure or worm castings before planting.

After planting, consistent moisture will prevent bitterness and bolting (going to seed too quickly), especially in warmer weather. In hot climates, you can achieve consistent moisture by planting in wicking beds or by covering your greens with shadecloth to create a cooler microclimate (this will also allow a greater range of greens to be grown).

Growing tips

Most greens can be planted out as seedlings 20–30cm apart.
Lots of annual greens are shallow rooted, and can be planted beneath annual vegies that take longer to grow (such as tomatoes, climbing beans and cabbages). They’ll benefit from mulching during hotter weather, especially when small. Avoid mulching in cooler weather or where slugs are a problem.
Greens are tastiest when grown quickly. Regular liquid feeding with seaweed or fish emulsion will boost growth.
Lettuce To make your lettuce crop last longer, only pick the mature leaves around the outside as you need them, rather than harvesting the whole plant. This will extend the plant’s life and you can keep picking new leaves as they regrow. With this method, most lettuce varieties will start to gradually grow a tall trunk and go to seed. Once this happens, cut the trunk off at the base and leave the roots in the ground. Within a few weeks, new smaller leaves will grow back and you can keep eating them.
Kale You can encourage kale plants to become perennial by harvesting just their mature leaves. This will encourage them to grow a tall trunk too (up to 1m high), with fresh leaves at the very top. They’ll keep producing well like this for around three years.

Tomatoes

Tomatoes come in all shapes and sizes and can thrive in pots or in the ground, so there really is something for everyone.

Soil

Tomatoes need well-drained soil and they are very hungry, so enrich the soil with compost or well-rotted manure before planting, but avoid too much high-nitrogen material (such as chicken manure), which will lead to abundant leaf growth but poor fruiting.
After planting, ensure you consistently water to avoid blossom-end rot. Also be mindful that overwatering during fruiting can lead to watery fruit and/or fruit splitting.

Growing tips

Plant tomato seedlings around 50cm apart. Seeds can be started in potting trays in a protected area, then planted out after 4–8 weeks.
When planting seedlings, prune off their lower leaves so you end up with a bare ‘trunk’. Dig a long shallow trench and plant them on their side with just their head poking out. This encourages extra roots to grow where the leaves used to be, and means they’re in the topsoil layer where more nutrients are available and where it is warmer, so they’ll pump more quickly.
Folks in tropical areas might be best to grow tomatoes in pots to avoid bacterial wilt, which can occur naturally in soil. You’ll know if you have this if your plant is happily growing but then suddenly wilts and dies. You can test whether a plant has it by putting a cutting of it in a glass of water. If the water turns white, you’ve got bacterial wilt.
Determinate (short bush) tomatoes are shorter plants that don’t need structures to climb on; they’ll fruit sooner but over a shorter period. Indeterminate (vine) tomatoes are taller plants that require support structures; they will fruit over a longer period.
You can support your tomato plants using a single stake with a cloth tie, a mesh cylinder, an A-frame trellis (which has more strength), or try the ‘Florida weave’.
Indeterminate tomatoes benefit from some pruning to create more airflow and to focus the plant’s energy into fruiting rather than leafing. Prune off the little suckers that pop up between the main ‘trunk’ and each branch.
Remove the lowest leaves to improve ventilation and reduce the risk of diseases such as blight and powdery mildew.
Mulch well, or grow companion living mulches – some good choices are basil, nasturtium or sweet alyssum. Tomatoes respond well to regular foliar feeding with a liquid fertiliser. Do this in the morning to prevent fungal diseases.
If you live in a vulnerable area, choose cultivars with thicker skins (such as cherry tomatoes), which are more resistant to Queensland fruit fly (Bactrocera tryoni).

Pumpkins

Pumpkins make a wonderfully productive addition to your edible garden. They can be a great groundcover in a young edible forest garden or can even be grown across a structure to provide shade and beauty!

Soil

Pumpkins are very hungry, so plant them in fertile soil with lots of aged manure and compost mixed throughout. Plant them on a shallow mound to assist with drainage.
They need consistent water, especially while flowers and fruit are forming. It’s best to avoid overhead watering, and to water early in the morning so the leaves dry quickly to avoid powdery mildew.

Growing tips

Sow seeds around 2m apart, at a depth of two to three times the seed’s length. For every one plant you want, use at least three seeds planted 5cm apart. Once they have sprouted, you can either weed out the weak ones or transplant them elsewhere. Plant seedlings 2m apart.
In cooler areas, start them indoors and only plant them out when the risk of frost has passed and soil temperatures are warm (greater than 15°C).
Mulch to keep the soil moist.
You can grow pumpkins either over a structure or along the ground. If on the ground, once the vines are more than 1m long you can remove a leaf and bury it – this encourages the plant to put down more roots so it can access more food and water.
If your baby pumpkins are going yellow and rotting, you might have a pollination problem. Plant lots of companion flowers to attract more beneficial insects in the garden, or try hand pollination. The same goes for zucchini plants.
Different varieties will have different maturation times. In cooler climates, choose smaller varieties that ripen earlier to ensure a harvest (such as ‘Baby Blue’, ‘Buttercup’, ‘Delicata’, ‘Golden Nugget’).
Harvest when the leaves are dying back, the stem is beginning to brown and the fruit sounds hollow when you tap it. Leave a long stem (5–10cm) on each pumpkin, and place the pumpkin on its side (so that water can’t collect around the stem) in the sun to ‘cure’ for around two weeks. Then store in a cool, ventilated space out of direct sunlight.
Long-storing varieties have thicker skin, such as ‘Golden Nugget’, ‘Queensland Blue’, ‘Baby Blue’, ‘Australian Butter’ and ‘Kent’. Shorter-storing varieties have thinner skin, and include ‘Butternut’, ‘Honeynut’, ‘Delicata’ and ‘Spaghetti Squash’.

This is an edited extract from Hannah Moloney’s latest book, Good Life Growing, $39.99, published by Affirm Press. Grab your copy to find out more about Hannah’s top 10 vegies to grow in Australia.

Photo by Natalie Mendham