Splitting Dahlias

With my cold zone 5b, it is necessary to dig up my dahlias in the fall and store them over the winter. Over the years, I’ve tried a few different methods to preserve my tubers. The method that works the best for me is to dig up my dahlia clumps, remove the excess soil from them, dry them for a few days, and then store them in whole, unsplit clumps in cardboard boxes in my basement. 

When the cold, dark days of January arrive, it is a great time to break out some sunshine and start splitting dahlia tubers. I start with one clump and use a high quality needle nose pruner to begin splitting off one tuber at a time from the clump (Photo 1). I ensure each tuber has an intact neck, an eye (Photo 2), and a body.

I discard any tubers with broken necks or missing eyes. It’s tempting to keep them all to see if they will be viable, but it is vital that each healthy tuber has the 3 needed parts. Each type of tuber can look very different. Some tubers are large and fat and others are small and skinny with every variation in between . 

After all the tubers are separated, I thoroughly wash them (Photo 3) and remove any dirt with a sprayer. Then they are laid out to dry for a couple of days (Photo 4). Once the tuber skin is dry enough to write on, I label each tuber with a Sharpie marker. They are then packed back into cardboard boxes with no packing material. I will take them back out in March to presprout them before planting or selling.