HAIL THE HYDRANGEA
These hardy stalwarts add colour well into November
WE JOINED the family on holiday in Cornwall last month. It rained a lot — it often does in Cornwall — but we enjoyed a beautiful day in Boscastle. The sapphire sea, rugged cliffs and riverside cottages were enchanting. But the stars of that sunny day were the ubiquitous mophead and lacecap hydrangeas.
I’ve never seen commonplace shrubs looking so regal — as though the tourist board positioned these horticultural delights to wow the visitors.
Hydrangeas look their best in late summer. But they produce early flowers, too, and if wellmanaged the shrubs can bloom from June to November.
They make a charming informal groups or can be placed as focal points. In Knightshayes, Devon, they’re naturalised in woodland: distant flashes of colour among the trees. And at the subtropical paradise of Trebah, by Cornwall’s Helford River, there are billowing banks of hydrangeas — like thunder clouds in blue and green.
Hydrangeas are easy to please, thriving in sun or part shade.
LACECAPS & MOPHEADS
GROW them in pots, large tubs or any fertile, moisture-retentive soil. I plant out in autumn, but you can buy containerised specimens to plant at any time.
They are low-maintenance, too. Prune once a year in March, removing last year’s dead flowers and weak stems, cutting back to a strong pair of buds.
To propagate new plants, take semi-ripe stem cuttings — barely mature shoots — between late August and mid September.
Root them in a cool and sheltered position. Hydrangeas do thrive in wet, breezy conditions, but don’t assume them to be water junkies.
The name is derived from Hydra — the multi- headed Greek monster slain by Heracles — not from ‘hydro’. And although they love the damp West Country, you’ll see them flourishing all over Britain.
There are about 80 wild species, many with great garden value. The most popular have been developed mainly from the Japanese variety Hydrangea macrophylla. These are the shrubs with big, mophead blooms or with elegant lacecaps.
The most colourful parts on mopheads are sterile bracts, each arranged in fours to make flower- like shapes. The true flowers are tiny and hidden among the bracts. With lacecap varieties, true flowers make up the centres, which are surrounded by an outer ring of bracts.
Few flowers die quite as elegantly. In August, they’re dewy fresh. But gradually pinks and blues darken and become suffused with antique hues of greens and duns before dying off.
FLORAL LONE RANGER
HYDRANGEAS also have unique characteristics. The flowers can be blue or pink, but only in some varieties. Colour is determined by the acidity or alkalinity of the soil. In acid soil, flowers will be blue or purplish pink. In alkaline conditions, they can only be pink or verging on purple.
If such varieties are containerised in ericaceous compost, they will be blue. But in neutral conditions, blueness can be enhanced with hydrangea colourant. This is based on ferrous sulphate and aluminium sulphate and available in garden centres or online.
Varieties with changeable colours include dark pink or blue Hamburg — a fine mophead with serrated bracts – and the lacecap Mariesii Perfecta. Altona has vivid pink or purple-blue mopheads and Blue Bonnet is pink if grown in alkaline soil.
There’s a stunning monster from Germany, Schloss Wackerbarth, whose large mopheads are an eyewatering mix of vivid green, wine pink and purple-blue.