Lifting Dahlias

There is always a debate as to whether you should lift your dahlias over winter or leave them in the ground. It really depends on where you live and the conditions you garden in. If you have mildish winters and don’t have a heavy, waterlogged soil, then nine times out of ten you will be able to leave them in the ground all winter, although giving them a protective mulch or compost or straw is always a good idea. I leave half my dahlias in each year and dig the rest up, before potting up the tubers the following spring so that I can put them back into the borders as plants in late spring or early summer.

Lifting them is easy. First cut back the foliage and stems right down to about 10cm from the base of the plant. By mid-November the plants will probably be starting to blacken and die back, and will need cutting back anyway, even if you plan to leave them in the ground. To dig them up, use a border fork and gently loosen the earth around the tubers, before using the cut stems to pull the clump of tubers from the ground. Brush off as much soil as you can from around the tubers and then wash them with a hose to clean them. At this stage I lay them out in a big wooden tray to dry, as well as checking each clump and cutting out any soft or damaged tubers. I will leave them or a week or two in my greenhouse to dry, before storing them in a box or crate of dry compost or sand. Keeping them as dry as possible over winter is the key, so they need to be kept somewhere cool and dry - in a shed, garage or greenhouse. If they get damp they will go mouldy and start rotting, and won’t be usable next year.

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