ON THE COVER Susie’s Garden

It’s horticultural show season, so our expert gardener turns her attention to that showiest of flowers – the dahlia

This week I’m celebrating dahlias. Richly coloured and sumptuous, they’re such exotic-looking flowers and they vary hugely in shape, size and even leaf colour. Dahlias are at their peak between now and the first frosts so it is a great time to visit gardens where they are grown and to take notes about which varieties you’d like to buy.

From the dramatic giants of the show bench to single cottage garden plants, dahlias keep giving providing you deadhead the spent blooms. Feed them once a fortnight with a liquid balanced feed – we use one made from seaweed – and make sure they get a very thorough watering once a week. It’s a good idea to stake them as they grow quickly and can be easily broken in the wind.

I’m lucky that our soil is so free-draining that we can leave dahlias in the ground all year round. I used to cut them down once the foliage was blackened by frost, lift and dry them, before storing in compost over winter. I then decided to risk

leaving some out, covering them with a deep mulch.

First I chopped their stems to cover the crowns, then laid a foot-deep mulch of organic matter – I was able to use spent hops but other types of mulch would do.

However, if you have heavy soil, then lifting will be necessary. It is the combination of winter cold and wet that rots the tubers, so although we had several frosts of -9C last winter, the light soil meant it didn’t hold water.

If you want named varieties, you need to buy them from a specialist nursery. They are not difficult from seed but you’ll get a mix of colours.

A packet of “Bishop’s Children” will produce a selection of dark-leaved, brilliantly flowered plants, excellent as cut flowers. I like to mix these dahlias through the flower borders where their dark foliage contrasts with the ferny leaves of fennel or the delicate wands of Stipa grasses. And if you choose single varieties with open blooms they’ll attract a mass of bees and butterflies.

Dahlia merckii – my favourite, a pretty lilac-pink with single flowers good for insects, said to be fairly hardy in Britain

Martina – a good cut flower, with pink flowers that darken to purple on the petal tips

Woodside Finale – fairly recently trialled, its lemon-yellow flowers are tipped orangey-red