How to grow hydrangeas – with National Trust garden consultant, Ian Wright

Know when and where to plant, prune and water these spectacular shrubs

There are around 75 species of hydrangeas and literally hundreds of cultivars. Not surprising, then, that there is sometimes confusion over how to look after these showy plants.

See also… How to look after roses – with tips from a National Trust gardening expert

Lucky then, that we have National Trust garden consultant, Ian Wright, on hand to show us how to identify and care for your hydrangeas.

WHERE TO PLANT HYDRANGEAS

Hydrangeas don’t respond well to drying out and will soon show signs of wilting.  Ideally, they enjoy morning sun but not the heat of the afternoon summer sun.  This is especially true for hydrangeas grown in pots.

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Hydrangeas line a path amongst the exotic planting in the garden at Overbeck’s, Salcombe, Devon. National Trust Images / Andrew Butler

Hydrangeas are quite forgiving and will tolerate full sun, but many will also be at home and flower in partial shade.  Soil type is also important – free draining, moist and fertile are best.

WHEN TO PRUNE HYDRANGEAS

Pruning your hydrangeas will help the formation of new flowers and promote good shape. But the key is to know what type you have.

If you have a ‘mophead’ type it may be Hydrangea macrophylla, which will develop that striking blue colour if planted in an acidic soil.

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Hydrangea arborescens ‘Annabelle’ growing in the Eagle Court at Tintinhull Gardens, Somerset. National Trust Images / Andrew Butler

One key to great flowering is to make sure you prune in the right way, at the right time of year. So, for mopheads you can cut the old flower head off in early spring, back to a pair of buds beneath last year’s flower.

For older established plants you could cut right back to the base up to two stems to encourage new growth, but perhaps not every year. Mulch in spring with a well-rotted compost to help conserve moisture – but don’t place the mulch right up to the stems.

If you have a climbing hydrangea such as Hydrangea anomala subsp. petiolaris, prune back the flower shoots straight after flowering in the summer, before next year’s flower shoots begin to form.

TIPS FOR KEEPING YOUR HYDRANGEAS HEALTHY

  • Plant carefully and in the right position to suit the species you have.
  • Don’t let hydrangeas dry out, but don’t over water – it’s all about being consistent.
  • Mulch the area around the plants to help conserve moisture and keep the soil cool in summer.
  • Protect your hydrangea against pests and diseases. One of the best ways to help prevent pests and diseases is to keep plants healthy and therefore more resilient.
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Photography / Amateur Gardening

IAN’S TOP THREE HYDRANGEAS

Hydrangea aspera Villosa Group

With its slightly hairy leaves, this lacecap has beautiful long-lasting flowers which makes it attractive to bees. It also has a nicely rounded form.

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Hydrangea aspera villosa at Hidcote, Gloucestershire. National Trust Images / Sarah Davis

See also… How to grow lavender – with inspiration from the National Trust’s Hidcote gardens

Hydrangea quercifolia ‘Snow Queen’

Also known as the oak-leaved hydrangea, its white flowers are arranged in conical panicles but with the added advantage that its leaves turn glorious red or purple in autumn.

Hydrangea macrophylla ‘Ayesha’

This has large but compact mophead flowers and is one of the few hydrangeas to have flowers with a slight scent. A nice hydrangea for a large patio container.

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