Sunflowers
Iconic, cheerful, and relatively easy to grow, sunflowers bring a splash of summer colour to any garden. Edible seeds are an added bonus for you and local wildlife.
Sunflowers seeds
£1.99 in the shop
Calendar
Sow
April – May, directly into well-prepared soil outdoors, or in pots indoors for an earlier start.
Plant out
May – early June, when seedlings are 15-30cm tall and all risk of frost has passed.
Harvest
August – October, once the back of the flower head turns yellow and seeds are plump.
Conditions
Sun
Full sun, 6–8 hours a day, essential for strong growth and large heads.
Water
Water regularly, especially during dry spells and when flowers are developing. Keep soil consistently moist but not waterlogged.
Soil
Fertile, well-drained soil, pH 6.0–7.5. Improve heavy clay with organic matter, sandy soil benefits from compost.
Spacing
30–60cm (1–2ft) apart, depending on variety and desired head size.
Containers
Yes, for dwarf and medium varieties, in pots at least 30cm (1ft) wide and deep.
Indoors
Can be started indoors 2-4 weeks before planting out, in individual pots.
Care and harvest
Feeding
Not strictly necessary in fertile soil, but a balanced liquid feed every few weeks can encourage larger flowers, especially for potted plants.
Pruning
Not typically pruned, but side shoots can be removed on single-stem varieties to encourage a larger main head.
Harvesting
Cut the head with about 30cm of stem once the back is yellow and seeds are plump. Hang upside down in a dry, airy place to dry completely.
Storage
Store dried seeds in an airtight container in a cool, dark place. Can also be roasted.
Good companions: Squash, Beans, Corn