How to grow brussels sprouts
Sure they’ve received a bad rap after being boiled to bits by generations past, but these fairy-sized cabbages deserve a second chance. Grilled, roasted, stir-fried or sauteed, brussels sprouts are a culinary dream team when accompanied with toasted hazelnuts, streaky bacon and a honey vinaigrette.
SOW AND GROW
Sow seeds: December to February in warm areas; September to October and January to February in cooler areas.
Transplant seedlings: February-March in warm areas; October-November and March-May in cooler areas.
Position: Full sun, six-plus hours a day.
Harvest: 12-20 weeks from seed.
GET STARTED
Brussels sprouts do better in colder climates because cooler conditions cause them to form tight hearts. A good frost sweetens them up, too, because the plants respond by pumping sugar into their cells to reduce water content and prevent the plant from dying.
In mild temperate climates, brussels sprouts can be grown to produce clusters of open ‘‘flower sprouts’’, but this crop is not really suitable for the warmest subtropical parts of the country.
However, in colder regions, sow in trays undercover in early spring to plant before Christmas for an early winter harvest (provided you get a cool summer), or in trays or direct mid to late summer to plant in autumn (although you want seedlings in the ground soon enough so they have a chance to get established before cold weather really hits). In more temperate regions, but where this crop is still viable, sow in summer and plant seedlings from late summer until early autumn.
STEP BY STEP
Plant seeds about 5–10mm deep and, if you are sowing direct, about 60cm apart. Seed should germinate in 6–10 days. If starting this crop in trays, transplant into individual pots when two sets of true leaves have formed. Seedlings can be planted outside when they are about 10cm high.
GROWING TIPS
Brussels sprouts prefer alkaline soils, so work lime into your soil a few weeks before planting. Avoid enriching your soil with fertilisers that are high in nitrogen as this can cause plants to produce leafy growth not sprouts. They are shallow rooted and top-heavy, growing to around 70cm tall, so firm the soil down when planting to prevent the plants from falling over as they grow. Plant them in a spot where they won’t be toppled by strong winds and stake if necessary.
Apply liquid fertiliser fortnightly. Once plants are 30–40cm tall and the buds along their upright stalks are starting to swell, pinch out the growing tip at the top of the plant (in the middle of the tuft of green leaves) so they expend all their energy on fattening the sprouts.
The sprouts form from the lower leaf axils first so start picking the sprouts from the bottom when they are around
2cm in diameter and tightly closed.Remove any yellowing leaves above the sprouts as you harvest.
STANDOUT VARIETIES
‘‘Jade F1’’ is an early variety (90-100 days to maturity) producing up to 80 solid, tasty, deep green sprouts. Being shorter than other varieties, it is more wind resistant. ‘‘Long Island Improved’’ is a trusty variety that is widely grown commercially. Purple-red heirloom ‘‘Red Ribs’’ has a mild, nutty flavour.
Kalettes, also sold as flower sprouts, are F1 hybrids bred by crossing kale with brussels sprouts. Try these if you have problems getting other varieties to form tight hearts or if you’re gardening in a warmer area.
TROUBLESHOOTING
Like all brassicas, brussels sprouts are targeted by white butterflies. Protect plants with netting. Aphids are also a problem and can be removed by hand or blasted off with the hose. Also like other brassicas, brussels sprouts are prone to club root, a soil-borne fungal disease. Crop rotation can help prevent it. Never plant brassicas in the same spot where other brassicas have been growing during the past three or four years.