How to grow hydrangeas

Read on to learn more about the different types of hydrangea, where and when to plant them, and how to care for them, plus watch out guide to growing hydrangeas, by David Hurrion, above.

How to grow hydrangeas

Jump to section:

• Where to grow hydrangeas
• How to care for hydrangeas
• How to prune hydrangeas
• How to propagate hydrangeas
• Hydrangea problem solving
• Best hydrangeas to grow
• Advice on buying hydrangeas

More on growing hydrangeas:

• How to grow climbing hydrangeas
• Nine white hydrangeas to grow
• Panicle hydrangeas to grow

Where to plant hydrangeas

Hydrangeas do best in moist, free-draining soil and dappled shade – not too sunny and not too shady. Avoid south-facing positions, especially if the soil is very dry. For a very shaded vertical surface, such as a north-facing wall, grow the climbing hydrangea Hydrangea anomala subsp. petiolaris. The young growth of hydrangeas is prone to frost damage in spring, so avoid planting in a frost pocket, and plant away from strong winds.

Hydrangeas will thrive in most soil types, including alkaline and acidic soil. However, the pH of the soil will change the colour of the flowers of some varieties. Some plants that usually offer pink flowers will appear blue if the soil is acidic.

When to plant hydrangeas

The best time to plant hydrangeas is in spring or autumn, when the soil is warm and moist. Planting in summer is possible, but you'll have to water more often to avoid the plant drying out before its roots can establish.

How to plant hydrangeas

Hydrangeas do best in fairly moist soil, so if your soil is light, bulk it up with moisture-retaining organic matter such as well-rotted manure or compost before planting. Water the plant well an hour or so before you plant it. Never plant a hydrangea deeper than it was in its original pot. Water in well. Mulch after planting, ideally with leaf mould; alternatively, use well-rotted manure or compost. Keep the plant well watered throughout its first spring and summer.

When planting climbing hydrangeas, train them initially onto galvanised wires. After a season of growth they'll make their own way as they have self-clinging aerial roots on their stems.

Watch Monty Don explain how to grow lacecap hydrangeas, in this clip from Gardeners' World:

Hydrangea care tips:

1. Water regularly, even weekly if necessary, throughout the plant's first growing season to help the roots establish.
2. Water hydrangeas with rainwater to help keep the flowerheads blue.
3. Hydrangeas do best in moist soil and can wilt in hot weather, so be ready to give extra water during hot spells in summer, especially if they are in full sun.
4. Mulch hydrangeas every year in spring with leaf mould, well-rotted manure or compost. Otherwise, it's usually best to avoid feeding them, as this encourages leafy growth at the expense of flowers.
5. You can change the colour of the flowers on lacecap and mophead hydrangeas, and Hydrangea serrata from pink to blue by feeding with a fertiliser low in phosphorus and high in potassium.
6. You can grow your plant in a pot of peat-free ericaceous compost and water with rainwater to keep the flowers blue.
7. Changing hydrangea flowers from blue to pink is trickier. You will need to raise the pH by adding dolomitic lime. It's quite common for a plant to produce a few different coloured flowers on one plant in the first year of growth. Few gardeners concern themselves with trying to change the flower colour – but it's interesting to know why plants may vary.

How to prune hydrangeas

Hydrangea macrophylla (lacecap and mophead hydrangeas) and Hydrangea serrata:

Prune in mid-spring. They produce their flowers on old wood, so don’t prune them back hard as you will lose this summer’s flowers. Traditionally, the old flowers are left on over winter as it protects the new growth beneath from cold. Cut back the flowerhead to just above the top set of plump buds forming under the dead flowerhead - this is where the new flowers will form. If you have an overgrown plant, cut off some of the older stems at the base to reduce congestion.

Hydrangea paniculata and Hydrangea aborescens:

Cut back in early spring. Pruning is not essential, but if left unpruned the plant will get taller each year, with most of the flowers at the top. These two types of hydrangea produce flowers on new wood, which means that you can cut them back harder without losing this year’s flowers. Prune last year’s growth back to a healthy framework between 30cm and 60cm in height, depending on how tall you want your plant to be. Prune to just above a pair of healthy buds on each stem.

Hydrangea aspera and Hydrangea quercifolia:

Lightly prune in spring – just remove old or crossing stems and old flowerheads.

Hydrangea petiolaris (climbing hydrangea):

Prune in summer after flowering for best results. Cut back the flowered shoots to a pair of new buds.

For more information on pruning hydrangeas, read our full guide on how to prune hydrangeas.

Watch this video for Monty’s tips on pruning different types of hydrangea:

How to propagate hydrangeas from cuttings

Take softwood hydrangea cuttings in spring. In the morning, look for young, non-flowering shoots that have three sets of leaves. For best results, prepare your cutting material straight away.

• Remove the two sets of lower leaves and shorten the stem of the cutting, cutting just below a node. Reduce the surface area of the remaining leaves by up to half.
• Insert the cuttings into a pot of gritty compost, or multi-purpose compost with plenty of perlite. More than one cutting can be placed in a pot, as long as the leaves don’t touch.
• Water in and cover with a clear plastic bag. Ideally, keep them in an unheated greenhouse.
• Once you see clear signs of growth, pot on plants, keeping them in a shady spot.

Growing hydrangeas: problem solving

Hydrangeas are very easy to grow and there are few problems that affect them.

A lack of flowers is likely to be due to pruning at the wrong time of year. Check the type of hydrangea that you have and follow our pruning advice, above.

Climbing hydrangea not flowering? Discover possible causes in our Quick Tips video, below:

Brown or blackened foliage or buds in spring are due to frost damage. Prevention is better than cure – plant your hydrangea in a sheltered spot away from frosts, leave the faded flowerheads on over winter and prune at the correct time. If your plant has been affected by frost, it's unlikely to have killed the whole plant. Give it time to recover when the weather warms up and only prune out dead or damaged areas in late spring.

Purple leaves can be due to a sudden decrease in temperature in spring or autumn. In spring, the leaves may turn purple if temperatures plummet but they should revert to their usual green once the weather has warmed. Late in the season, the leaves of some hydrangeas change colour as the plant begins to go dormant in autumn. Purple leaves can also be a sign of phosphorus deficiency, which is particularly common on plants where the flower colour has changed. Adjusting the pH or applying a fertiliser high in phosphorus may help.

Hydrangea scale is a sap-sucking insect found on hydrangeas. In severe cases, it can cause poor growth and leaf loss. You may spot the eggs, covered in a white waxy material, in early summer. The mature scale insects look like brown blobs. If the problem is serious, spray in July with an organic insecticide based on plant oils or fatty acids.

Vine weevils can attack hydrangeas that are growing in pots. You may see chunks bitten out of the leaves, but the main problem takes place beneath the soil, where the C-shaped white grubs eat the roots. This can cause the plant to decline rapidly.

• How to control vine weevil

Nine of the best hydrangeas to grow

Hydrangea macrophylla 'Ayesha'

Mopheads are the hydrangeas to grow if you want bold colour. The blooms last for months, finally ageing to muted tones before drying to brown over the winter. Held in small, silvery lavender flowerheads, the florets of Hydrangea macrophylla 'Ayesha' have unusual curled edges.

Height x Spread: 1.5m x 1.5m

• Buy Hydrangea macrophylla 'Ayesha' from Thompson & Morgan

Hydrangea macrophylla 'Zebra'

Large, white mophead flowers, near-black stems and rich-green leaves give this plant a dramatic look.

H x S: 1m x 1m

• Buy Hydrangea macrophylla 'Zebra' from Crocus and Waitrose

Hydrangea macrophylla Miss Saori

You'll get two flushes of the double pink and white flowers from this RHS Chelsea Plant of the Year 2014 winner.

H x S: 1m x 1m

• Buy Hydrangea macrophylla Miss Saori from Thompson & Morgan, Van Meuwen and Crocus

Hydrangea macrophylla 'Veitchii'

Lacecap varieties are more delicate than mopheads and are generally very hardy. Hydrangea macrophylla 'Veitchii' is a free-flowering lacecap with large, white bracts that turn pink with age, set around a mass of small flowers that start off blue but then fade to violet.

H x S: 1.6m x 1.6m

• Buy Hydrangea macrophylla 'Veitchii' from Burncoose

Hydrangea macrophylla 'Jogasaki'

The bracts range from palest pink through lilac to icy blue. It offers vibrant autumn leaf colour, too.

H x S: 1.5m x 2m

• Buy Hydrangea macrophylla 'Jogasaki' from Burncoose

Hydrangea serrata 'Bluebird'

As well as pink or blue florets around flat clusters of tiny, blue flowers, this lacecap hydrangea offers fiery autumn foliage.

H x S: 1.2m x 1.2m

• Buy Hydrangea serrata 'Bluebird' from Thompson & Morgan, Crocus and Waitrose

Hydrangea paniculata 'Phantom'

Hydrangea paniculata varieties have large, conical flowerheads that start off white or green, then become pink or even red. The large flowerheads of Hydrangea paniculata 'Phantom' have yellow-tinged tips.

H x S: 1.8 x 2m

• Buy Hydrangea paniculata 'Phantom' from Thompson & Morgan and Suttons

Hydrangea arborescens 'Annabelle'

Hydrangea aborescens varieties have huge domed flowerheads in white or pink. Full of impact, the flowerheads of Hydrangea aborescens 'Annabelle' fade to a lime-green.

H x S: 2.5m x 2.5m (shorter with regular pruning)

• Buy Hydrangea arborescens 'Annabelle' from Crocus, Thompson & Morgan and Waitrose

Hydrangea quercifolia

Hydrangea quercifolia varieties have large, oak-shaped leaves that turn fiery shades in autumn, along with large conical flowerheads.

H x S: 2m x 2.5m

• Buy Hydrangea quercifolia from Burncoose, Gardening Express and Waitrose

Hydrangea paniculata 'Limelight'

Limelight hydrangea is an upright shrub with yellow-green leaves, grey-green stems and large, green flowers, which fade to creamy white before turning pink in autumn.

H x S: 2.5m x 2.5m

• Buy Hydrangea paniculata 'Limelight' from Thompson & Morgan, Suttons and Crocus