How to Store & Keep Dahlias in the UK
- 1). Trim each tuber stalk until it is 5 inches long. Loosen the dirt around each tuber using a gardening fork. Push the shovel into the soil at an angle close to the dahlia and pull on the stalk to lift it out of the ground. It is best to dig up the tubers before the onset of hard frost in winter. Dahlias can survive mild winters in the ground but, as the weather is unpredictable, it is often best to dig them up anyway.
- 2). Rinse the tubers in tap water to remove the soil and put them upside down to dry. They can be hung upside down using a clothes peg and a washing line or by putting them upside down in a glass. Be gentle when you rinse, and make sure you do not remove the bulb's outer layer.
- 3). Cut back the roots using a knife until they are 1 inch long. Put the tubers in a cool, dry place. Leave for three to five days to dry. Check regularly as drying time varies with climate. Do not let the outside skin of the tuber flake off or become wrinkled.
- 4). Dust the tubers with sulphur. This reduces the chance of them rotting. Put all the tubers in a plastic storage bin, and cover them with vermiculite. Leave them in cool dry place such as a shed. For best results, the storage temperature should be 40 to 50 degrees Fahrenheit.
- 5). Check the dahlias once a month. Discard any that are starting to rot. Replant the tubers in the spring when they start to grow green shoots.
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