One of the great additions to a summer garden is what we call the tender bulbs. For instance dahlias, cannas, gladiolus, and tuber roses have tender bulbs. All of these bulbs are planted in the spring after the danger of frost. They come up, grow and provide us with a summer of color. But then in the fall, they need to be dug up because they won’t survive the winter. The best time to dig these tender bulbs is after the first frost, or when the foliage starts to yellow or die down naturally.
It’s a relatively simple process to dig these tender bulbs. Get in there with a shovel and lift the bulb. Take your hands and remove as much of the soil as possible, or you can take a little stream of water and wash the soil off the bulbs. Then you’ll need to remove and cut the foliage back. The debris that you cut off your spring flowering bulbs can be put into the compost pile. There are usually relatively few insects and disease on the dahlias and cannas, and they’re a good, green moist source to help the compost pile work during the winter months.
Then, we’re going to leave the bulbs in a dry, warm area for a week or two, such as your garage. The purpose of leaving them in the warm area is to cure the bulbs. It brings the excess moisture out of the tuber or bulb, so that it will store during the winter.
The bulbs need to be stores where they won’t freeze. So, for most of, that’s going to be in a basement or garage. It’s best to have the temperature somewhere between fifty and sixty degrees. The bulbs can either be left shallow in a pan or tray, or they can be covered with vermiculite or peat moss to help hold a little bit of moisture.
Check the bulbs occasionally during the winter months. If you have any rot or decay, you’ll want to remove those. And then in the spring, you’re ready to bring your bulbs back out for another season of color. So, you can enjoy your glads, your cannas and dahlias for another great year in the garden.
This feature story prepared with Dennis Patton, Kansas State University Research and Extension Horticulture Agent, Johnson County. For more information, visit your local county extension office or visit our website at KansasGreenYards.org.