Hydrangea Hydrangeas have large blooms that bring flamboyant colour to the garden in late summer and autumn. They're easy to grow, dependable and improve with age. Use them in big, bold groups in the border, or even in large containers.

In this article

Recommended varieties

Growing tips

Where to see them

Mophead hydrangeas (with rounded heads of large flowers) come from Japan, where the native species with lacecap flowers (flattened heads of small flowers) have been grown for hundreds of years.

When these plants reached the west in the 18th century they caused a sensation, initially being treated as tender and grown indoors.

The increase in new varieties with improved colour began 100 years ago in French, German and English nurseries. There's now a bewildering choice and even the experts can't always distinguish between them.

• H. macrophylla 'Quadricolor': lacecap with unique, yellow and cream-splashed foliage. Also look at 'Mariesii' types, particularly the award-winning trio of 'Grandiflora', 'Lilacina' and 'Perfecta'. The first has pink to blue flowers with a whiter centre, the second mauve-pink to blue flowers, and the third lilac to rich blue flowers. All grow to about 1.5m (5ft). H. m. 'Nigra' has shiny black stems and creamy flowers that become pinky lilac with age. Note that on acid soils macrophyllas are lilac, elsewhere they're pink. Only the whites stay white
• H. paniculata: one of the showiest hydrangeas with dramatically large flowers. 'Unique' is initially greeny white, but later develops a pink flush that deepens over autumn. It can grow more than 1.8m (6ft) in one year but won't get out of hand if pruned hard annually and is ideal for a small garden. The Royal Horticultural Society has given 'Unique' its Award of Garden Merit (AGM).
• H. aspera Villosa Group: large, velvety foliage above a huge lacecap and late summer flower-heads the size of dinner plates. Large, pale pink florets form the outer ring surrounding a domed centre of fertile, fuzzy lilac flowers that bees love. In the right conditions it may reach more than 3m (10ft) high and wide. Has been awarded the AGM.
• H. quercifolia: the deeply lobed foliage resembles oak leaves, gradually becoming burnished with red and deep purple in autumn. Looks fabulous with red Kaffir lilies and silvery pink Japanese anemones. Tapering, white flowers appear from summer well into autumn, with the plant growing to 2m (6ft) high. 'Snow Queen' holds its large flower-heads more upright than most hydrangeas, while 'Snow Flake' produces double blooms and requires a sheltered corner with light shade.
• H. 'Preziosa': pink or pale lilac blooms gradually become speckled and eventually suffused with crimson. Foliage turns a warm, coppery red in autumn. Grows to 1.5m (5ft) high.

The following climbing hydrangeas are worth trying if you have a large, sturdy bare wall (possibly in light shade) that needs an evergreen covering.

• H. anomala subsp. petiolaris: clambers up walls like ivy and clamps itself to the brickwork. Has attractive mahogany brown stems and lush, bright green, deciduous foliage. The lacecap flowers last just a few weeks in summer.

Soils for colour

The soil type determines the flower colour - acid, for example, produces blue flowers. To create blue on a limey soil, use a blueing compound composed of aluminium sulphate. However, the results won't compare with plants growing in acid soil.

Alternatively, grow a compact variety, such as 'Blue Bird', in a large container filled with lime-free compost and supplement its liquid feed with a blueing compound.

Site and watering

Hydrangeas are true survivors and can often be seen flowering in overgrown or neglected gardens.

Mopheads and lacecaps prefer dappled shade against a north- or west-facing wall. If it's too bright they're likely to scorch.

Their leafy shoots need plenty of moisture during the summer. Apply a mulch to drier soils to lock in moisture and promote decent-size flowers.

Plants also need to be sheltered from cold winds, which can frazzle new foliage during the spring.

Pruning

Pruning isn't essential but can be done each spring as new shoots appear. With established plants, just remove one-third of the older, less productive stems and cut back old flowering stems to a strong pair of buds.

Leave old flower-heads on over winter to provide frost protection to new growth. The brown papery domes look fantastic when covered with frost.

Left unpruned, hydrangeas will continue to bloom but the size of the flower-heads will be reduced by the overcrowded stems.

H. paniculata needs to be cut back completely each spring.

National Collections of hydrangeas:

PR Smith
Derby City Parks
15 Stores Road, Derby
Derbyshire DE21 4BD
Tel: 01332 715560

S Wingett
The Garden House, Erbistock
Wrexham LL13 ODL
Tel: 01978 781149

S Newman
Lakeland Horticultural Society at Holebird
Patterdale Road, Windermere
Cumbria LA23 1NP
Tel: 01539 446008
Website: www.holehirdgardens.org.uk