Gardening: The dos and don'ts of dahlias – our tips for growing real showstoppers
:: Add organic matter before you plant: Use well-rotted manure, but if you can't get that, use compost, digging it into the soil the previous autumn or in early spring, to give it plenty of time to break down.
:: Get your timing right: Plant your tubers 10-15cm (4-6in) deep in their flowering position in late May or early June in fertile, well-drained soil in full sun. You can start tubers off early, March or April, in large pots filled with multi-purpose potting compost and put them in a light, frost-free place, keeping the compost moist.
:: Right plant, right place: "You could dedicate an area to dahlias as they look fantastic as a crowd," says expert Katie Kingett. "They also look good in a herbaceous border. You want to avoid planting them near the base of a tree, so that they can establish. Keep them clear of weeds and keep an eye out for any pests, as slugs and aphids love them."
:: Give them support: "As they grow, support is very important. Support them individually with canes or if you've a larger section of dahlias, put posts around them with netting running along the top which the dahlias grow through and which will provide the support they need. Once they are established, you won't see the netting," says Kingett.
:: Feed them: Dahlias are also hungry - so will benefit from regular feeding - and thirsty. When growing in containers, plant them in rich, soil-based compost such as John Innes No. 2. In summer, you'll need to water them every day.
:: Watch for earwigs: Earwigs can cause damage to flower petals but can be trapped by putting an upturned flower pot stuffed with straw, on canes, and shaking it every morning.
:: Disbud to encourage better blooms: Pinch out growing tips once plants reach a height of about 40cm (16in) to encourage branching. Once they are beginning to bud up, take the two smaller buds out below the central flower, which will create a more impressive bloom for cutting. Once that begins, you need to do it regularly - cutting and deadheading will help prolong the flowering to October, until the first frosts of the autumn.