If you don’t know how to overwinter summer bulbs, it’s really not that difficult to do.
Fall is certainly bulb-planting time for the spring bloomers, but it’s also the time to dig up and store non-hardy bulbs. These include such bulbs as dahlias, gladioli, tuberous begonias, canna and calla lilies.
How to overwinter summer bulbs – step by step:
Keep your dahlia tubers in a cool place over the winter
You could grow these plants as annuals and forget about them.
However, stored properly in a cool dark place, summer bulbs and tubers can survive the winter, ready to be potted up in spring, or planted into the garden for more summer blooms.
Here’s what to do:
- Dig bulbs or tubers up after frost has blackened foliage. Carefully remove as much soil as you can.
- Cut the leaves off, leaving a stem about an inch or two long. Leaves and stems are not needed, as the plants are going to be dormant and not making any growth through the winter.
- You can either carefully wash the soil off the tubers or bulbs, or just let it dry and work it off by hand later.
- Leave bulbs or tubers exposed to air in a frost-free place for a couple of weeks. Any remaining stem should be dry before going into storage, otherwise rot could develop.
- Store in vermiculite or dry peat (available at garden centers) in paper bags or cardboard boxes in a cool, frost free place at 40 to 50°F (5-10°C).
- Dahlia tubers are prone to drying up somewhat, and these should be stored in slightly moistened peat moss. Check them through the winter, and if they’ve shriveled, moisten the peat moss. Some authorities suggest plumping shriveled dahlia bulbs up in a bucket of water overnight. If you do this, let them dry thoroughly before you put them back into storage.