Sow direct into a well-prepared planting site with good Top Soil from March until July. Make shallow drills and sprinkle the seed about 2 cm apart. Cover with fine soil, or purchase a good quality Top Soil.
You should allow about 30 cm between rows. Thin the seedlings to about 8-10 cm apart. Succession sow throughout the season to keep you well supplied.
You can start beetroot off in modules inside and they can be multisown into a good quality Seed & Cutting compost. To do this put a pinch of seed in each module and plant out as a bunch taking the full plug of starter compost with the seedlings to ensure less root disruption.
They will grow happily together, pushing out from the centre, although the individual beets will be smaller. Harvest baby beets at the size of a golf ball and main crop ones at about tennis ball size. Any bigger and they are likely to get woody.