Sow every three weeks from March to June for a continuous crop in summer, and then again in late summer/early autumn for a winter crop.
Sow in rows 30cm apart at a depth of 1cm.
When big enough, thin out to about 25cm between plants (eating the thinnings).
Either use the Cut and Come Again method, or harvest whole plants.
Baby leaves can be used in salads; larger leaves should be cooked.