Hydrangeas are much-loved deciduous hardy shrubs, some of which are climbers. Their huge flower heads come in a range of shapes, from large balls to cones. The most popular types are mophead and lacecap. Hydrangea flower colours range from blue, white, red through to pink. If you plant more than one type in the garden you can plan for flowers from April to October. The foliage on some can be dramatic in autumn, most notable is Hydrangea quercifolia.
Take a look at our comprehensive guide on how to grow hydrangeas. Learn more about the different types of hydrangea, where and when to plant hydrangeas and how to care for them.
The most familiar hydrangeas in our gardens are mopheads and lacecaps, with large, rounded flower heads in shades of white, blue and pink in summer and autumn. In recent years, however, many new hydrangeas have been introduced. There are compact varieties for smaller spaces or containers, double-flowered and bi-coloured choices, and varieties that offer a change of colour as the flowers mature. There are even varieties that flower on old and new wood, flowering twice. Some have scented flowers; others have beautiful autumn foliage.
This means there’s a hydrangea for every garden, whether you’re looking for a more traditional style for a cottage garden or shrub border, or a more contemporary or urban look.
There are several hydrangea types:
Hydrangea macrophylla – this includes the popular mophead (hortensia) types, with huge domed heads, and lacecap varieties, which have smaller, flatter and more delicate flowers. The acidity of the soil affects the colour of macrophylla hydrangeas – acid soils tend to produce blue flowers, and alkaline soil pink flowers (white flowers aren’t affected). The colour of the flowers varies on neutral soils.
Hydrangea paniculata – panicle hydrangeas. These have conical flowers in more subtle shades of white and lime green and pink. They can cope with more sunshine than macrophylla types.
Hydrangea serrata – compact varieties with delicate flowers. Good for smaller gardens or containers.
Hydrangea aborescens – large shrubs with huge domed flowerheads. The main variety available in the UK is ‘Annabelle’.
Hydrangea quercifolia – oak-leafed hydrangea. It has white, cone shaped flowers and, as its name suggests, oak-like leaves that turn red and orange in autumn.
Hydrangea aspera – rough leafed hydrangea. Rough, hairy leaves and flattened flower heads that look like lacecaps. Attractive to bees and butterflies.
Hydrangea anomala subsp. petiolaris, Hydrangea seemannii and Hydrangea serratifolia – climbing hydrangeas suitable for growing up a shady wall or fence. H. seemannii and Hydrangea serratifolia are evergreen.
How to grow hydrangeas
Hydrangeas are woodland plants, so most grow best in a partially shaded, sheltered spot. Do not allow the soil to dry out, especially in hot weather. Mulch annually with well-rotted manure or compost. Most hydrangeas are pruned in spring.
Hydrangeas: jump links
- Where to grow hydrangeas
- How to care for hydrangeas
- How to propagate hydrangeas
- Hydrangea problem-solving
- Types of hydrangea to grow
- Advice on buying hydrangeas
More on growing hydrangeas:
Where to plant hydrangeas
Hydrangeas do best in moist, well-drained 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 spot, such as a north-facing wall, grow the climbing hydrangea Hydrangea anomala subsp. petiolaris. The young growth 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 spring or autumn, when the soil is warm and moist. Planting in summer is doable, but you’ll have to keep an eye on moisture levels in the soil.
How to plant hydrangeas
Hydrangeas like 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 is fine. 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 roots.
Watch Monty Don’s guide to planting lacecap hydrangeas, in this clip from Gardeners’ World:
Caring for hydrangeas
Mulch hydrangeas every year in spring, with leaf mould, well-rotted manure or compost. They don’t need feeding, as this encourages leafy growth at the expense of flowers. Hydrangeas have a tendency to wilt in hot weather so keep well watered during hot spells in summer. Water with rainwater to keep hydrangeas blue.
You can change the colour of some hydrangea flowers from pink to blue by feeding with a fertiliser low in phosphorous and high in potassium. Alternatively, you can grow your plant in a pot of peat-free ericaceous compost and water with rain water to keep it blue.
To change 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.
Hydrangea macrophylla (lacecap and mophead hydrangeas) and Hydrangea serrata are pruned in mid-spring. They produce their flowers on old wood, so don’t prune them back hard, or this summer’s flowers would be lost. Traditionally, the old flowers are left on over winter as it protects the new growth beneath. Cut back the flower head to just above the top set of plump buds that are forming under the dead flower head. This is where the new flowers will form. If you have an overgrown plant, cut some of the stems off at the base.
Hydrangea paniculata and Hydrangea aborescens are cut back in early spring. Pruning is not essential, but left unpruned the plant will get taller 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 that’s between 30cm and 60cm high, 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 are also lightly pruned in spring – just remove old or crossing stems and old flower heads.
The climbing hydrangea, Hydrangea petiolaris is best pruned in summer after flowering. Cut back the flowered shoots to a pair of new buds.
Watch Monty’s tips for pruning different types of hydrangea here:
How to propagate hydrangeas
Take softwood cuttings from hydrangeas in spring. In the morning look for young, non-flowering shoots that have three sets of leaves. For best results prepare cutting material straight away. Alternatively, keep them in a plastic bag in a cool shed.
Remove the two sets of lower leaves and shorten the stem of the cutting. Cut just below a node. Insert the cuttings into a pot of cutting compost. 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.
See How to take hydrangea cuttings for more detail on taking hydrangea cuttings.
Growing hydrangeas: problem solving
Hydrangeas are very easy to grow and there are few pests and diseases that hinder them. Pot-grown hydrangeas may be prone to vine weevil attack and some plants will be damaged by frost. To avoid frost damage, leave the faded flowerheads on the plant and prune at the correct time.
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.
Climbing hydrangea not flowering? Discover possible causes in our Quick Tips video:
Advice for buying hydrangeas
- Check that hydrangeas grow well in your area before buying – a quick look at local front gardens will give you an idea of soil type and suitability
- Bear in mind that the flowers of some hydrangeas may change colour once planted in garden soil – consider growing in a pot of ericaceous compost if you’re fussy about flower colour
- Check the eventual height and spread of the hydrangea, and its general growing requirements before buying, to ensure you have the perfect conditions for your hydrangea to thrive
Where to buy hydrangeas online
Great hydrangeas to grow
- Hydrangea paniculata ‘Limelight’ – lime-green clusters of flowers from July to September. Height of 1.5m
- Hydrangea paniculata ‘Sundae Fraise’ – a compact variety with white and lime green flowers that turn pink from August onwards. Height 1.2m
- Hydrangea macrophylla ‘Veitchii’ – an attractive lacecap type with flowers from July to September. White florets surround a cluster of tiny blue flowers. Reaches 1.5m
- Hydrangea arborescens ‘Annabelle’ – giant clusters of lime-green/white flowers from July to October. Height 1.5m
- Hydrangea anomala subsp. petiolaris – climber that self-clings. Grows almost anywhere including a north-facing wall. White flowers from June to August. Height 15m
- Hydrangea ‘Enziandom’ – produces some of the deepest blue flowers when grown on an acid soil. Flowers from July to October. Height 2m
- Hydrangea arborescens subsp. discolor ‘Sterilis’’ – compact shrub covered in elegant creamy-white flower heads from July to September.