About
In summer, it bears huge singular flowers with velvety petals of dark bronze and deep dark centres. A fast-growing annual with broad, oval to heart-shaped, roughly hairy leaves. The flowers attract bees and the seeds that follow provide food for finches.
About the genus
Helianthus can be tall, erect annuals, tuberous or rhizomatous perennials, with coarse simple leaves and large daisy-like flower-heads
Growing conditions
SunlightFull sun
Soil typeChalk, Clay, Loam, Sand
Soil pHNeutral, Alkaline
Soil moistureMoist but well-drained
AspectSouth-facing, West-facing
ExposureSheltered
UK hardinessH4
Plant details
Plant typeAnnual Biennial
HabitColumnar upright
FoliageDeciduous
Height1.5-2.5 metres
Spread0.1-0.5 metres
Time to full height1 year
Suggested usesWildlife gardens, Cottage and informal garden
Care notes
CultivationGrow in moderately fertile, neutral to alkaline, humus-rich, moist but well-drained soil in full sun. This plant was included in the RHS Helianthus (sunflower) trial 2024
PruningCut back old stems after flowering as they die down for the winter
PropagationPropagate 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
Pest resistanceMay be susceptible to slugs and snails
Disease resistanceMay be susceptible to Powdery mildews and sclerotinia diseases