Hydrangea arborescens 'Annabelle'
Every summer this wonderful plant surprises with its huge balls of pure white flowers. It grows into a large shrub but it makes a perfect specimen plant in the Long Border and Spiral Garden at Rosemoor where we combine it with herbaceous perennials such as Sedum spectabile 'Stardust', asters, Crocosmia × crocosmiiflora 'Lady Hamilton', Kniphofia 'Bees' Sunset' AGM and Geranium renardii AGM to provide contrast in form and colour. We also use in it a woodland setting in Lock's Trail.
Vital statistics
- Common name
- Hydrangea 'Annabelle'
- Family
- Hydrangeaceae
- Height & spread
- Up to 2.5m (8ft) high and wide
- Form
- Deciduous shrub
- Soil
- Moist, well-drained moderately fertile, humus-rich
- Aspect
- Full sun or partial shade
- Hardiness
- Fully hardy
Hydrangea
This is a genus of about 100 species of deciduous and evergreen shrubs, trees and climbers from eastern Asia and the Americas.
The leaves are large and oval, with serrated edges and are a fresh, bright green colour. The flower heads consist of very small fertile flowers surrounded by larger, four-petalled, sterile florets and can be rounded (mopheads), conical or flat-topped (lacecaps). The colours include white, red, pink, purple and blue. The non-white flowers are affected by the pH of the soil, with acid soils producing blue flowers and alkaline ones, pink.
While hydrangeas are grown mainly for their flowers, they also have interesting, flaky, peeling bark when mature, and attractive foliage with good autumn colour.
The name derives from two Greek words: hydor, meaning water, and angos, meaning a vase or receptacle, alluding to the shape of the seed capsule.
Hydrangeas make excellent specimen plants or group plantings and the climbers are very good on shaded walls.
They may cause mild stomach upset if ingested and contact with foliage may aggravate skin allergies.
Hydrangea arborescens 'Annabelle'
Hydrangea arborescens is a bushy, deciduous shrub with broadly ovate (oval tapered) leaves up to 18cm long, and is from the eastern USA. Its flowers are borne in large domed or flattened clusters of mainly fertile flowers in summer, and these can be 15cm (6in) across, if not bigger. It is more tolerant of extreme conditions than some other hydrangeas.
'Annabelle' has flower heads the size of dinner plates; big balls of flowers up to 20-25cm (8-10in) across. The flowers gradually fade from creamy white until they are papery-brown seed heads, but these stand well for months making the seed heads a potential winter feature.
A recent introduction from the USA is 'Incrediball', said to be a modern replacement for 'Annabelle' with stronger and more floriferous stems.
Cultivation
- Grow in moist but well-drained, moderately fertile, humus-rich soil in sun or partial shade.
- Needs shelter from cold, drying winds.
- Prune to remove frost damaged shoots, and remove deadheads in early spring.
- Prone to grey mould, hydrangea virus, powdery mildew, leaf spot, honey fungus, aphids, red spider mites scale insects, vine weevils and capsid bugs.
Propagation
- Sow seed in containers in a cold frame in spring.
- Root softwood cuttings in early summer, or hardwood cuttings in winter.
AGM
The RHS Woody Plant Committee awarded Hydrangea arborescens 'Annabelle' an Award of Garden Merit and described it as a:
'Small, bushy deciduous shrub with broadly oval leaves and very large, rounded heads of white sterile flowers to 25cm across.'