Helianthus annuus 'Giant Single'
sunflower 'Giant Single'
A tall and large, fast-growing annual with oval to heart-shaped, roughly hairy green leaves. In summer it produces a wonderfully large sunny yellow flower with a chocolate brown centre. Great for seeing who can grow the tallest and attracting bees and 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
Neutral, AlkalineColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Yellow Brown | Green | ||
| Autumn | Yellow Brown | Green | ||
| Winter |
Position
- Full sun
Aspect
South–facing or West–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
Unresolved
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 a cane to support the weight of the bloom and grow tall
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
- Cottage and informal garden
- City and courtyard gardens
- Wildlife gardens
- Flower borders and beds
Pruning
Cut back after flowering or once the flower heads have dried, then collect the seed or share them with the birds
Pests
Diseases
May be susceptible to powdery mildews and sclerotinia diseases
Get involved
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