Sow seed on the surface of a good free-draining damp seed compost. Cover with a very fine sprinkling of compost or vermiculite. Place in apropagator or seal container inside a polythene bag and place at 18-25°C (65-77°F) until after germination which usually takes 7-14 days. Do not exclude light as this helps germination.
Transplant seedlings when large enough to handle into trays or 7.5cm (3in) pots. Grow on in cooler conditions for 10-15 days before planting out after all risk of frost, 45cm (18in) apart.