Space plants at least 36 inches apart. Staking the plants is recommended.

Do brassicas need staking?

Staking brussels is essential on anything but the most sheltered of sites. Earthing up around stems of brussels and heavy-headed cabbages helps to stop rocking.

How do I support brassicas?

Windbreak fencing can work well. Brussels sprouts are very susceptible to windrock. If they're in the open try earthing up the stem, staking or growing in triangles and tying the plants together so they support each other.