Most bulbs prefer not to be disturbed and can be left in the ground for many years. But beware of overcrowding. When too many bulbs try to occupy the same space, they will be less vigorous and flowers will be fewer and smaller, an indication that it's time to transplant them.
How to Store Fall Bulbs
Once the foliage dies back or matures in the late spring or early summer, the bulb is dormant. You can tell the plant is dormant when the foliage is brown and papery and can easily be pulled free. Summer is the dormant period for spring-blooming bulbs. As the foliage dies back, the roots that nourish the bulbs also die back. With fall rains, the bulb comes out of summer dormancy and roots begin to grow again to provide the bulb nutrients and moisture. Once the spring bulbs enter dormancy, the time is right to dig the bulbs if needed. Some bulbs benefit from digging to divide the bulbs and spread them out over the bed.
If you lift your spring-flowering bulbs, they should be stored in a well-ventilated place and replanted in the fall. Every five years daffodils and crocus should be dug and replanted to prevent overcrowding. The first sign of overcrowding will be a decrease in the flower size, uneven bloom and uneven plant height. When this occurs, dig, spread bulbs out and replant immediately.
How to Store Spring Bulbs
Less hardy bulbs such as dahlias, begonias and gladiolus should be lifted each fall. As soon as frost has blackened foliage, gently spade up the bulbs, being careful not to cut into the bulbs and damage them. If you prefer to lift the bulbs before frost has hit, you can dig your bulbs early and store them in a well-ventilated, frost-free area until they are dry. Just let the leaves remain on the bulbs until they become dry.
Most bulbs should be dried for about a week before you prepare them for storage. Pull loose any remaining foliage, shake the bulbs gently to remove any clinging soil, dust them with fungicide powder to prevent rot and place them in unsealed paper bags or old nylon stockings with some dry peat moss to keep the bulbs from touching one another. Store them away from sunlight in a cool, dry basement, cellar, garage or shed at 60° to 65°F. Avoid temperatures below 50° or above 70°F unless different instructions are given for a particular bulb. Follow specific storing instructions for tender bulbs, such as cannas and calla lilies.
Growing Bulbs in Warm Zones
Because tulips, crocuses, irises, and hyacinths require cool soil conditions before blooming, you must give them an "artificial winter." Lift (dig up) your bulbs every year after foliage yellows and place them in the refrigerator for 8-12 weeks before replanting. Never store bulbs with fresh fruit.
Bulb Storage: A Step-By-Step Guide on How to Dig and Store Plant Bulbs
In most colder zones, you must dig up bulbs like begonias, dahlias, and gladioli before fall frost, winter them indoors and plant again in spring. Learn how to overwinter tender bulbs and bareroots with these steps:
After the first light frost and before the soil freezes, dig the bulbs out of the soil. When digging the bulbs and tubers, be sure to work several inches away from the main stems so you don't harm the roots.
Gently lift the bulbs from the ground. Shake off the loose dirt and rinse with water gently.
Place the bulbs and tubers in a dry, shaded spot (like a garage) until the outside of the tuber feels dry. Do not let them freeze.
After a few days, inspect the bulbs for signs of disease or decay. If a bulb or tuber is in poor condition or infected, discard it. For any bulbs you are keeping, cut off their remaining foliage and stems.
To store your bulbs, lay them in uncovered shallow flats or boxes filled with peat moss, sawdust or vermiculite. You can put the containers in an unheated garage or basement. Storage temperatures may range from 45°-60°F depending on the type of bulb.
Check monthly to make sure they are not drying out and shriveling. They should stay plump until spring planting time, so you may have to sprinkle them with a little water to keep the right moisture. Too much water will cause mold.
At the proper planting time for your area, plant the bulb or tuber as you normally would.
How long can bulbs be stored?
If stored correctly, most bulbs can be kept out of the ground for about 12 months.
Where should you store bulbs?
Flower bulbs can be kept on a tray in a cool, dark, dry, well-ventilated area until you can plant them. Do not store them at temperatures below 39 degrees F. Bareroots should be stored in dry peat moss or wood shavings in a brown paper bag, open crate, netted bag or even old pantyhose. Store at 50-55 degrees F in a dry location until it's time to replant the bareroots. Do not store bulbs and bareroots in an air-tight container.
Do flower bulbs go bad?
Yes, flower bulbs can get mushy or become shriveled. They can also get moldy if not stored correctly. If this happens, simply throw the bulbs away.
How do you replant bulbs?
Replant bulbs the same way you would plant them normally. Generally, you should plant bulbs two to three times as deep as the bulbs is tall.