The Gardening Coach

PUBLISHED: 12:02 12 May 2014

dahlia flower cluster

dahlia flower cluster


Judy Shardlow’s guide to gardening in May

Dahlias are a must-have summer plant. They flower from June to October, grow in full sun and part shade and come in a huge range of colours and shapes. They also make beautiful cut flowers, and if you keep cutting, more flowers will grow.

There’s something for everyone. Some blooms are spiky (cactus and semi-cactus) and there are ruffles, pom-poms or just beautiful simple anemone-flowered heads. I particularly like the dramatic cactus-flowered blooms, such as the vivid purple Ambition or the dramatic black-crimson ruffles of Rip City. These are popular garden dahlias, but recently a fairly new cultivar has caught my eye, Blue Bayou, a striking anemone-flowered dahlia that is dusky lilac blue with a deeper red centre. It’s a stunner and will grow to a metre tall.

Dahlia’s can be bought at this time of year as rooted cuttings, which may look quite small, but will quickly grow into a large plant. They need very rich soil to sustain their impressive flowering habit, so add plenty of well-rotted organic matter to soil before planting. Young plants can be planted out at the end of May and will need staking as they grow.

May gardening jobs

Get young plants and vegetables ready for the great outdoors <bold> by hardening off the foliage in a cold frame.

Increase plant stocks <bold> by taking softwood cuttings from plants such as Penstemon, Fuchsia and Lavender.

Plant runner and French bean seeds <bold> in the vegetable garden now or young bean plants out at the end of May to avoid frost.

Tie-in climbers. <bold> Prune back any clematis that has already flowered and tie-in clematis and other climbers that are yet to flower as they put on new growth.

Feed bulbs. Bulbs have done their bit for this year but don’t cut the leaves back, as this will limit growth next year. Just remove seed-heads and allow foliage to die back naturally.

Judy Shardlow is a Herts-based gardening coach

01438 833858

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