Helianthus annuus 'Red Sun'
sunflower 'Red Sun'
A fast-growing annual with broad, oval to heart-shaped, roughly hairy leaves. In summer, it bears huge singular flowers with velvety petals of dark bronze and deep dark centres. The flowers attract bees and the seeds that follow provide food for finches
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Size
Ultimate height
1.5–2.5 metresTime to ultimate height
1 yearUltimate spread
0.1–0.5 metresGrowing conditions
Moisture
Moist but well–drainedpH
Neutral, AlkalineColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Bronze Orange | Green | ||
| Autumn | Bronze Orange | Green | ||
| Winter |
Position
- Full sun
Aspect
South–facing or West–facing
Exposure
Sheltered Hardiness
H4Botanical details
- Family
- Asteraceae
- Native to the UK
- 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
- Wildlife gardens
- Cottage and informal garden
- Flower borders and beds
- Cut flowers
- Wall side borders
Pruning
Cut back old stems after flowering as they die down for the winter
Pests
Diseases
May be susceptible to Powdery mildews and sclerotinia diseases
Get involved
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