How to Store Flower Bulbs During the Winter

A bulb is a rounded part at the base of a plant's stem that stores energy while the plant is dormant. At the center of the bulb is the plant shoot itself, which is surrounded by layers of carbohydrates. Some bulbs, called tunicate bulbs, are covered in a papery skin called a tunic; imbricate bulbs have no tunic. Corms, tubers, tuberous roots, and rhizomes are all bulb-like storage organs but are not, in fact, true bulbs.

There are two types of true bulbs that gardeners can grow, each suited to different conditions.

1. 1. Tender bulbs: Summer flowering bulbs, such as dahlias, begonias, cannas, elephant ears, and gladiolus, cannot survive underground in the winter. When the ground freezes, these tender bulbs may rot if left in the ground. Once tender summer flowering bulbs have wilted in the fall, dig them up before the first frost and store them indoors during the winter.
2. 2. Hardy bulbs: Not all bulbs need to be stored indoors during the winter. Spring bulbs, such as tulips, daffodils, crocuses, and hyacinths, actually benefit from their time in the cold winter soil. When their foliage wilts in the summer or fall, you can trim away some of the dead plant matter, but leave the bulbs in the ground to bloom next spring. Some gardeners dig up hardy bulbs anyway, to divide or replace overcrowded bulbs for maximum yield.

Tender bulbs go into storage before the first frost of winter, and you should plant them in spring—meaning they spend about four months in storage. Most bulbs won't last more than 12 months, so if you forget to plant tender bulbs in the spring, you’re better off planting them late rather than saving them for a year until next spring.

When the cold-weather months come around, it’s time to store your tender bulbs.

1. 1. Harvest bulbs. Wait to dig up bulbs until all of the plant's foliage has died. This should be sometime in the fall before the first frost. If you wait until after the first real frost, the bulbs may rot. Trim the foliage down to about six inches and gently dig the bulbs out of the ground, being careful not to damage them. Compost any damaged bulbs.
2. 2. Dry bulbs. Allow the bulbs to air-dry indoors on paper towels or newspapers for at least two weeks. Choose a dry place with good air circulation. Test a bulb’s dryness by trimming the stem. (Leave at least two inches of stem, or the bulb may start to root from the sprouting end.) If the stem is moist inside, the bulbs need more time to dry.
3. 3. Pack bulbs. Store tender bulbs in paper bags, reusable mesh bags, or cardboard boxes with air holes poked in for air circulation. Fill the container with peat moss, sawdust, or vermiculite—enough to cover each bulb by one inch. Make sure the bulbs have enough air circulation to prevent rotting.
4. 4. Store bulbs in a dry place. Store your flower bulbs in a dry place until you're ready to replant them. Aim for a storage temperature of 45 to 50 degrees Fahrenheit, such as a garage or refrigerator. Store tropical bulbs in a slightly warmer area.
5. 5. Plant bulbs. Planting time will depend on the variety of bulb, but you’ll generally plant tender summer bulbs after the last frost. If your main bulb has several smaller daughter bulbs attached to it, you can divide it before planting. Healthy bulbs should be large, firm, and free of fungus or rot. Discard any mushy or cracked bulbs.

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