PLANT it NOW
BRASSICAS
The cooler months are coming and it’s time to prepare the patch for a seasonal changeover. Brassicas dominate the domain, and early action is the key to getting good results, especially for those that are slow to mature, such as cabbage, cauliflower, broccoli and brussels sprouts. Some varieties need four or five months of cool weather to come to fruition, and while it still feels too warm to be growing them, plants started now will ensure you have a delicious midwinter harvest. The trick is to put extra effort into keeping them cool until high temperatures ease.
Direct sowing into warm soil is likely to lead to disappointment. Brassica seed won’t germinate in the heat, and keeping soil adequately moist will be a challenge. Even if they do germinate, the delicate little seedlings will surely suffer terminal heatstroke in the patch on a hot day.
Sowing in punnets is the way to go, because containers can be moved about to control conditions. They don’t need direct sunlight to germinate, so you can place punnets in a cool spot under a shady tree, or in a cool room indoors. Once they come up, normally within a week, they will need exposure to direct sun, to avoid plants becoming long, leggy and weak. Find a spot that gets 3–4 hours of direct early-morning sun, which is the least intense, with shade from late morning.
When starting seed in single-cell punnets, moisten the seed-raising mix, dribble seed into shallow drills about 7–10mm deep, and backfill. Soon after they germinate, prick out individual seedlings and plant them in small, individual pots. For multicell punnets, sow 2–3 seeds per cell and remove all but the strongest seedling for growing on. Keep seedlings cool and moist, and liquid-fertilise them once a week.
If you prefer to buy seedlings, that’s great – you’ll get a few weeks’ head start! Pot up and care for them as described above and wait until the temperature starts to cool before planting out in the patch. Once they are in the ground, be prepared to protect plants with shadecloth on days when the heat returns.