Sow indoors, February-June, 0.5cm (¼”) deep, in a tray of compost. Water well and place in a cold frame, unheated greenhouse, or on a warm kitchen windowsill. Keep moist. Seedlings usually appear in 21-42 days. Transplant individually, when large enough to handle, to 7.5cm (3″) pots. Always hold by a leaf, never by the stem. Gradually accustom young plants to outside conditions (avoid frosts), before planting out, into well-drained soil in a sheltered spot, August-October, 40cm (16″) apart. If plants are large enough to transplant outside in autumn, they are best protected with cloches through the winter. Alternatively, plant out, March-May, the following spring. Flowers: June-September, the following year.