Sow seeds on the surface of a good, free-draining, damp seed compost. Lightly cover, 3mm (1/8in) deep, with vermiculite or compost. Place container in a propagator or seal inside a polythene bag at a temperature of 20-30?C (68-86?F) until after germination which usually takes 7-21 days. Direct sow outside from late April once the soil has warmed. Sow seeds thinly at a depth of 3mm (1/16in).