When the summer comes to an end and summer bloomers finish flowering, it's time to ensure they can overwinter frost-free. Depending on the type of bulb, you can either leave them in the ground or dig them up. In this blog, you'll find everything you need to know about storing summer bulbs.

Dig Them Up or Leave Them in the Ground?

Most summer bloomers, such as Dahlias, Cannas, and Begonias, will freeze if left in the ground. For these types, it’s better to dig them up and store them in a frost-free place. However, there are differences in the storage location and the time when you can bring the bulbs and tubers indoors. You can read about it below.

Storing in a Pot

Cannas and Eucomis prefer to be brought indoors early and kept in a location between 10 and 12 degrees Celsius. Eucomis can dry out in the pot, but for Cannas, you should first trim the stems down to about 10 centimeters. The rhizomes can be stored in a large pot with potting soil, ensuring they don’t dry out.

Proper Drying

Gladioli and Begonias need to be well-dried first. Before drying Gladioli, it’s important to cut the leaves down to 10 centimeters. Then, you can let the leaf remains dry. Don’t forget to remove the old corm! After drying, store both types of bulbs in a place where the temperature is between 5 and 10 degrees Celsius, in coco peat or dry peat.

Wait for the First Frost

For Dahlias, it’s better to leave them outside as long as possible. This is because they form good tubers and store a lot of reserves at low temperatures. Once the foliage turns black from the first frost, you can dig them up. Crocosmia can stay in the ground as long as the soil doesn't get too wet during the winter.

Regularly Check Their Status

When storing summer bloomers, it’s important to check on the bulbs and tubers monthly. If the storage area is too damp, they can start to mold. In this case, replace the material in which they are stored. Don’t forget to let them dry thoroughly before putting them back! If the environment is too dry or too warm, they may shrivel and feel no longer firm. You can try lightly misting them with a plant spray in this case.

Storing bulbs properly for the winter is quite an art. Keep in mind that it is still a natural product, so we cannot guarantee that the summer bloomers will flower again the following year.

Pre-sprouting and Planting Summer Bloomers

You can pre-sprout summer bloomers or wait to plant them after the last frost. Various summer bloomers, such as Tuberous Begonia and Dahlia, can be pre-sprouted from the end of February. To do this, plant them in a pot and place them in a bright spot with a temperature of about 18 degrees Celsius. From mid-May (after the last frost), you can move the pots outside or plant the pre-sprouted plants directly into the ground. The reason for pre-sprouting is to ensure you have fully grown plants by mid-May, rather than just bare bulbs or tubers. Pre-sprouting is not mandatory, though. They will also bloom beautifully if planted after the last frost. Planting after the last frost is important because summer bloomers cannot tolerate cold, and there is a chance they won't survive.

Did you know it's also possible to store spring bulbs? Read our blog with all the tips on storing spring flowering bulbs!