divide & plant dahlias

Dahlias have enjoyed a revival in the popularity stakes in recent years, as gardeners have rediscovered their cheerful and plentiful blooms. With summer just around the corner, this is a good time to plant dahlias. They are grown from tubers, which are available in packets at local garden centres. Always check carefully to make sure the tubers are firm and healthy. Don’t buy any that are soft, shrivelled or rotten. You can also buy tubers directly from online suppliers.

If you have stored your own dahlia tubers over the winter, inspect each clump and remove any sections that are mouldy or clearly dead. Next, decide if you want to divide the clump before replanting. Clumps that have healthy tubers can be split into halves or quarters, or sometimes separated into individual tubers. The important thing to remember is that each fat, finger-shaped tuber must retain some of the central section that joins the tubers (called the eye), because that’s

where the new growth will shoot from. Use a sharp knife or pair of secateurs to cut up the clump, making sure you clean the blades and wipe them with methylated spirits to disinfect them before moving to the next clump.

Plant dahlia tubers into a sunny, well-drained spot that’s protected from strong winds. If it’s a tall or large-flowered variety, it will need a supporting stake, and this should go in before planting. Watch out for snails and slugs, keep the plants well watered in hot weather and, best of all, enjoy the wonderful display of colour in late summer and autumn.