Broccoli Growing Guide
Broccoli, also known as sprouting broccoli, is a delicious, nutritious, and easy-to-grow member of the cabbage family. It forms multiple small clusters of purple or white buds on long, leafy stems. Depending on the variety and sowing time, it can provide harvests from summer onwards, with winter varieties offering valuable crops through to spring. Traditional varieties can grow up to 90cm tall and wide and provide repeated harvests for up to two months. It can also be grown as microgreens on a sunny windowsill, producing sprouts in about two weeks.
This guidance applies to the crop in general. Individual varieties and local conditions can differ.
Planting information
Broccoli seeds can be sown from February to July. Sow indoors from February or outdoors from April, in small batches several weeks apart for a continuous harvest. For indoor sowing, use a modular seed tray with peat-free seed compost, sow two seeds per module 2cm deep, and thin to one strong seedling once established. For outdoor sowing in a seedbed, make a shallow drill 2cm deep and sow seeds about 7.5cm apart. If sowing in their final position, sow three seeds every 60-80cm, then thin to one strong seedling. Protect young plants from slugs and snails. Microgreens can be sown at any time of year into a small seed tray of damp peat-free seed compost. Young plants 10-15cm tall, whether sown indoors, in a seedbed, or bought as plug plants, should be transplanted to their final growing position from mid-spring until late summer. Hardening off indoor-sown plants is recommended. Plant them deeper than they were growing previously, with the lowest leaves at the soil surface, to encourage deep rooting. Space plants 60-80cm apart, with a similar distance between rows. Cover young plants with insect-proof mesh or biodegradable fleece to reduce insect damage.
Harvesting information
Regular sowings can provide harvests from June through to March, with plants taking 4-10 months to start cropping and then providing pickings for up to two months. Harvest broccoli when the small heads, or spears, are well formed but still tightly in bud. Remove the whole shoot by cutting at the base, including about 10cm of stem and any small leaves, all of which are edible. Harvest the central spear first, which encourages more shoots to form on the side, providing continuous pickings over several weeks. Check plants regularly to harvest before the bud clusters begin to open.
Storage information
Broccoli is best used as fresh as possible. It can be kept in the fridge for a few days and freezes well for longer storage.