Helianthus annuus
common sunflower
A tall, fast-growing annual with broad, oval to heart-shaped, roughly hairy leaves 10-40cm long. In summer it bears huge flowers up to 30cm across with bright yellow petals and dark brownish or purplish centres. The flowers attract bees and the seeds that follow provide food for finches
Size
Ultimate height
2.5–4 metresTime to ultimate height
1 yearUltimate spread
0.5–1 metresGrowing conditions
Moisture
Moist but well–drainedpH
Alkaline, NeutralColour & scent
Stem | Flower | Foliage | Fruit | |
Spring | Green | |||
---|---|---|---|---|
Summer | Brown Yellow | Green | ||
Autumn | Green | |||
Winter |
Position
- Full sun
Aspect
West–facing or South–facing
Exposure
Sheltered Hardiness
H4Botanical details
- Family
- Asteraceae
- Native to GB / Ireland
- No
- Foliage
- Deciduous
- Habit
- Columnar upright
- Genus
Helianthus can be tall, erect annuals, tuberous or rhizomatous perennials, with coarse simple leaves and large daisy-like flower-heads
- Name status
Correct
How to grow
Cultivation
Grow in a moderately fertile, humus-rich, moist but well-drained, neutral to alkaline soil in full sun. Will flower best in a long, hot summer. May need support
Propagation
Propagate by seed or division. Divide established clumps every 2-4 years to both increase plants and retain vigour. See sowing seeds indoors for further advice
Suggested planting locations and garden types
- Wildlife gardens
- Cottage and informal garden
- Flower borders and beds
- Cut flowers
- Wall side borders
Pruning
No pruning required
Pests
Diseases
May be affected by powdery mildews and sclerotinia diseases
Get involved
The Royal Horticultural Society is the UK’s leading gardening charity. We aim to enrich everyone’s life through plants, and make the UK a greener and more beautiful place.