Green Comet
Broccoli in the US

Broccoli likes a cool start, so timing is everything. You can get going from early spring for a summer crop, or mid-summer for a fall harvest, depending on your USDA zone. For folks in zone 3, think April to July; zone 4, April to August; zone 5, March to August; zone 6, March to August; zone 7, February to September; zone 8, February to September; zone 9, January to October; and zone 10, January to November. You can sow seeds 1/2 inch (1 cm) deep, either direct into the soil or in trays indoors. Keep them spaced about 1 inch (2.5 cm) apart if starting indoors, then thin later. A bit of succession sowing every few weeks works a treat for a continuous harvest.

If you've started seeds indoors, once they've got a couple of true leaves, prick them out into individual pots. Give them a good few weeks to harden off outside before planting them out properly. Don't rush it; wait until all danger of your last frost has passed. Space your plants about 18 inches (45 cm) apart in the ground, with 2 feet (60 cm) between rows. Broccoli can do okay in big containers too, as long as they get plenty of sun and aren't cramped.