Sow March to April on the surface of lightly firmed, moist seed compost in pots or trays. Lightly cover the seed with vermiculite. Place sown pots or trays in a propagator or warm place, and keep at a temperature of between 20-25C (68-77F) . After sowing, do not exclude light as this helps germination. Keep the surface of the compost moist but not waterlogged; germination will usually take 14-21 days. When large enough to handle transplant seedlings into 7.5cm (3in) pots or trays.
Gradually acclimatise plants to cooler conditions for a few weeks before planting out after all risk of frost, 30cm (12in) apart.