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.
Gradually acclimatise over 7-10 days before transplanting into warm, well-drained, humus-rich soil in full sun, with shelter from winds. Choose a spot that receives at least 6 hours of direct sun per day and prepare the soil in advance, adding plenty of well-rotted manure or compost. Plant at a minimum of 120cm (4ft) apart between plants. Pile the soil into mounds about 15cm (6in) high. Plant each pumpkin plant on top of a mound to ensure good drainage and keep them well watered until they are established. Feed with a general fertiliser a few weeks after planting.