University of Illinois Extension
Bulbs & More

Questions & Answers

What should be done with yellowing tulip leaves?

These should be left in place until they’re almost completely yellow, about late June. Then use scissors and cut them to the ground. The leaves should be left on as long as they are green because they are making food for next year’s flowers. If the leaves are unsightly, you could tie them together loosely and plant annuals in between.

How should late-arriving bulbs be handled?

Plant them immediately. Do not attempt to carry them over until spring. Plant in an area where the soil is not frozen, such as near the foundation of your home. Be sure to mulch. Transplant to a permanent site, if needed, next summer. If you are anticipating a late shipment, you can mulch the prospective planting site to keep the soil from freezing until after the bulbs are planted. You can also force them indoors.

orange dahlias

How often do you have to dig up hardy bulbs?

Dig up hardy bulbs only as often as you desire to move them to a new location, or when they are becoming crowded and/or flower production decreases.

How should I fertilize hardy bulbs?

The most important time to fertilize is right after the bulbs bloom. Use 2 pounds per 100 square feet of a commercial fertilizer such as 5-10-5 or 12-12-12. Work fertilizer lightly into the soil surface.

How should I protect young tulip leaves from a late, hard frost?

Don’t! The leaves are usually not damaged by temporary cold and freezing temperatures.

I received a pot of blooming tulips for Easter. How should I treat them when they’re done flowering?

You can either throw them out immediately or make an effort to rebloom them outdoors again in two to three years. It is very unlikely that they will bloom again the year after you received them. If you want to save the bulbs, cut off the flower stalks after flowering and continue to water as needed until the leaves turn yellow. Then withhold water, cut leaves back and put the entire pot in a cool (50°F), dark place until August.

In August, plant the bulbs separately outdoors. Be sure to fertilize.

How can I keep squirrels or moles from eating	bulbs?

How can I keep squirrels or moles from eating bulbs?

Bulbs are not usually a preferred food of squirrels, moles, mice or other rodents, but they can take a liking to them. Moles are often unfairly blamed when bulbs disappear. More often, the culprit is field mice that also use mole tunnels. They most often attack tulips, crocus and gladioli and rarely eat daffodils, alliums or colchicums.

The mouse problem is a difficult one. Sprinkling dried blood, tobacco or a similar repellent on the ground is effective only until the next rain washes it away. Owning a cat that enjoys walking through your flower beds is a very effective deterrent to rodents.

Where you are determined to try bulbs, make a small "cage" of 1/2-inch mesh screen. Place several bulbs inside, root plate down and bury the entire cage at the proper depth. Rodents won’t be able to chew through, but roots and stems can grow out.

Why didn’t my bulbs bloom this spring?

There are only a few reasons that bulbs do not flower. If the bulbs were planted last fall, dig down to see if they rotted in the soil. If they did, the planting site is poorly drained. If you don’t find the bulbs at all or see only withered green leaves on the ground, perhaps a rodent ate them.

If leaves appeared with no flowers, question the source and the storage technique. Bulbs purchased at an end of year sale may not have been stored properly and the flower bud may have been dead at the time of purchase. Before buying many bulbs on sale, buy one or two and cut them in half longitudinally to make sure the flower bud is alive. If it is brown or dried up, the bulbs will not flower next spring. This is a fair test of the quality of the remaining bulbs. If you stored the bulbs near apples or in a garage, ethylene gas may have caused the flowers to abort.

If the bulbs were planted in a previous fall, they may have received insufficient light or the leaves may have been cut back prematurely last year, resulting in insufficient food reserves to support flowering this year.

With some bulbs, including tulips and hyacinths, decline is expected after two to three years or even sooner. These bulbs are best treated as annuals in a display garden.

Which side of the bulb goes up at planting time?

Which side of the bulb goes up at planting time?

Be sure to identify either the root plate and face it downwards, or last year’s shriveled flower stalk, which goes upwards. Compare with pictures or diagrams or dig up a bulbs to see which end is which.

When can I plant summer-flowering bulbs?

Plant after the frost-free date in your area to avoid damage to emerging shoots and rotting of tubers in cold soil. Many tender bulbs may be started indoors in spring.

Can dahlias planted in spring as bedding plants be saved at the end of the season?

Yes, you can save dahlia tubers from year to year. By the end of the season, bedding plant dahlias will have produced tubers large enough to dig in fall and save over winter for the next season.

Frequently Asked Questions About Bulbs