There’s a change in the air and with this comes a change with what we grow in the garden. Now is the perfect time to plant autumn vegies, like brassicas. Also known as cruciferous vegetables or cole crops. This family includes broccoli, bok choy, cauliflower, cabbage, kale, and kohlrabi. In the kitchen they’re perfect additions to winter stews, stir-fries, warm salads or roast dinners. If you have never roasted a whole cauliflower head, you haven’t lived!
Brassicas are easy to grow in raised garden beds or large pots – although you may need a few pots as most of them love their own space to grow and spread. I recommend getting started now as it can take 12-16 weeks to harvest – depending on what you grow.
What they like
All brassicas love full sun, so choose a spot where they will receive at least six hours of full sun a day. Ensure the spot is protected from strong winds as this can cause plants to topple over or worse, uprooted. If you’re growing directly in the garden enrich the soil with plenty of organic matter, like compost, aged manure and blood and bone. Dig it well into the soil, turning it over to a depth of at least 20 centimetres. Ideally, you should do this at least one week prior to planting. For pots use a premium quality potting mix and choose a container at least 30 centimetres wide and deep.
As time is of the essence, plant seedlings. They’re available from all good nurseries and garden centres. Although for plants with a shorter harvest time (like kale and bok choy) you can sow them from seed. Plant according to label directions and water in well.
Tip! Sow successive crops every 3-4 weeks to extend your harvest window.
How to care for them
As the plants grow ensure you water regularly so they do not dry out. Mulch around the base of plants with sugarcane mulch or lucerne to help keep the soil moist. Applying an organic-based liquid fertiliser once a fortnight will also help promote strong, healthy growth.
The larvae of the cabbage white butterfly and cabbage moth are two common pests of brassicas. You may not see them either – they camouflage quite well on the leaves – but you will see their trail of destruction. Holes or large chunks missing from leaves are a good sign your plants are being attacked by these pests. Spray with an organic insecticide, like Dipel, to help control them. There is no withholding period, so it’s safe to spray and eat on the same day but always wash your vegies before eating.
When to harvest
For leafy crops like bok choy and kale, begin harvesting the outer leaves from 4-6 weeks. I find it’s best to harvest as you need but if you prefer to use the whole bok choy slice it off at the base and it will reshoot, albeit smaller.
To harvest broccoli cut the large central head once its firm, typically 12-16 weeks from planting. The harvest doesn’t end there though – smaller side shoots will form that can be cut and enjoyed. If you want a continual harvest of broccoli plant broccolini. The florets are smaller but plentiful plus they come in purple, too.
Cauliflower is best harvested when the ‘curds’ or heads are full size, usually 12-16 weeks from planting, depending on the cultivar. Keep the plant label so you know exactly when to pick. To help prevent them from turning yellow and spoiling, fold the outer leaves over the heads and secure.