A giant among annuals. Give them plenty of room and you will be rewarded with plants up to 3m (10ft) tall with huge yellow flowers often 30cm(12in) in diameter. Useful to grow against an unsightly shed or fence. Birds love the seeds so grow a few plants close to the house and watch them feed in the autumn. Flowers summer. Height 8-10ft. Culinary note: Some parts of these flowers are edible. Try toasting the seed kernels for a healthy snack. Companion planting: Try growing sunflowers with chives to deter aphids.
Sow early spring to early summer outdoors where they are to flower. Prepare the ground well and rake to a fine tilth before sowing. Sow 12mm (0.5in) deep in rows 45cm (18in) apart. For really giant sunflowers, sow them indoors in late winter/early spring, individually in 7.5cm (3in) pots at a temperature of 15-18C (60-65F). Grow on in good light conditions, harden off and plant out when all risk of frost has passed.
They prefer a sunny open site but will grow in most sites and soils.