(This article first appeared in the March print edition published Feb. 28)
During the spring season, it’s not uncommon for temperatures to play tricks. One week you can wear shorts – the following week you need gloves and earmuffs. Plants are also affected by the extremes in temperatures. Although some of the flower and leaf buds may be damaged when the temperature drops back to the norm, mature plants will survive. Bulbs are more tender than woody plants and cause even experienced gardeners concern when their green foliage begins peaking through the ground during a winter warm spell. Spring-blooming bulbs are tough and usually not damaged by conflicting temperatures. In fact, bulbs like snowdrops and crocuses are supposed to come up early, often when there is still snow on the ground. Applying a 3-inch layer of mulch to bulb beds in the fall, before the ground freezes, will help regulate soil temperatures and may help avoid premature growth in late winter.
If you purchased or received bulbs late in the year, I hope you planted them. It is always best to plant bulbs in the fall to give them as much time as possible to develop a good root system before spring bloom. Find an area in your landscape where the soil is not frozen, such as near the foundation of your home, plant at the proper depth, and mulch the bed. The first year, you may only have a few blooms but the following spring, you should have a full show. Remember there is a difference between spring blooming (i.e., Hyacinths, Daffodils, Crocus) and summer blooming (i.e., Caladium, Canna, Dahlia) bulbs. Summer blooming bulbs should not be planted until after the frost-free date (typically April 15 in Henderson) to avoid damaging emerging shoots or rotting bulbs in the cold soil.
Sometimes bulbs may not bloom as expected. Some of the more likely reasons for this problem include poorly drained soil. Dig up your bulb to see if it has rotted in the soil. Poorly drained soil subjects bulbs to disease pressure to which there is no cure. Remove decayed bulbs and try improving the soil drainage or select a new planting location.
Rodents like squirrels, chipmunks, and voles will feed on certain bulbs. Their favorite bulbs are tulips, crocus and gladiolus, while daffodils and hyacinths are rarely bothered. Some techniques to try include enclosing bulbs in a hardware cloth box (1/2 inch mesh) or commercially available bulb box; lay wire mesh over the bulb bed in the fall when they are most susceptible; try feeding the squirrels in the fall to keep them full; or try sprinkling repellents on the ground.
If leaves appeared but the bulb did not bloom, it may have been improperly stored. Before buying a large quantity of bulbs, cut a few in half longitudinally. If the flower bud is brown or dried up, the bulbs will not flower in the spring. Also, storing bulbs near fruit that releases ethylene gas may cause the flower bud to abort.
Bulbs gather nutrients from their leaves and cutting those back too early after blooming may result in insufficient food reserves to support next year’s blooms. Maintaining foliage for about six weeks will reduce this problem. Add 2 pounds of a commercial fertilizer such as 5-10-5 or 12-12-12 per 100 square feet of bed just after the blooming period to help older bulbs build food reserves.
If you notice flowers becoming smaller or less abundant, your bulbs may need dividing. Bulbs should be dug after the foliage dies back completely. They can be separated, respaced and replanted immediately. Keep in mind that some varieties may skip a year when divided.
Bulbs are a wonderful addition to your landscape and with proper care, will perform well for many years. Follow these suggestions and I am sure you can be successful!