Sow seeds on their sides in small 7.5cm (3in) pots of seed compost at a depth of about 2.5cm (1in). Place them in a propagator or seal the pots inside a polythene bag at a temperature of 20°C (68°F) until germination, which takes 5-7 days. Once germinated, grow plants on for about 4 weeks until they are large enough to be transplanted outdoors.