About
This tall and large, fast-growing annual with oval to heart-shaped, roughly hairy green leaves. In summer, they produce wonderfully large sunny yellow flower with a chocolate brown centre up to 30cm (12in) across . Great for seeing who can grow the tallest and for attracting bees, 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
Height2.5-4 metres
Spread0.5-1 metres
Time to full height1 year
Suggested usesWildlife gardens, Cottage and informal garden
Care notes
CultivationGrow 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
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