Sow in trays or pots on a windowsill or in a greenhouse at approximately 20-25ºC (68-77ºF) onto firmed, good quality, moist compost. Do not exclude light or allow to dry out (germination 15-20 days.) Transplant seedlings into trays, 8cm (3") apart and grow on. Plant out in the autumn 30-45cm (12-18") apart to flower the following year. Alternatively sow direct outside in a shallow groove, barely covering the fine seed. Thin to 15cm (6") and grow on before final planting.