Dear Aggie: My tulips are no longer blooming, what should I do?
Tulip bulbs divide naturally each year, resulting in smaller, less vigorous bulbs with little or no flowers. The solution is to either divide and replant these small bulbs, knowing that it may be several years before they fully bloom – or to replace them with new ones. According to the New York Botanical Garden, for most varieties, you can plan for 4 to 7 years before you need to plant new bulbs.
It can take 6 to 7 years for tulips to start blooming when grown from seeds. To ensure large, uniform blooms from a known variety, most gardeners purchase new bulbs every few years. After their first year, new tulip bulbs begin to divide. Without division, their size decreases every year. These tiny bulbs become crowded and compete for both light and nutrients, resulting in small flowers or no flowers at all.
If your tulips bloom in the first year but not in the second, there may be several factors at play. There may be plenty of shade because tulips require full sunlight. You may have cut the foliage too early, starving the bulb of energy. Be sure to allow the bulbs to turn yellow and wilt naturally.
If you prefer to save bulbs rather than replace them, dig them up and separate them every three to five years. The benefit is that you will have more bulbs to replant and you can save money. The downside is that young bulbs may not bloom for several years.
Wait until the foliage turns yellow and wilts naturally. Carefully dig them around the base without cutting off the bulbs. Brush off dirt. Separate the younger (offset) bulbs from the older (parent) bulbs. Look over them and dispose of any bulbs that are moldy or damaged. Place it on newspaper or a dry surface for two to three weeks. Double-check and discard any soft or damaged bulbs. Place them in mesh bags in a cool, dry area.
When fall comes, you can replant them. Make sure to choose areas that have good drainage. Consider adding bulb compost or bone meal to the soil before replanting. If you only have a few bulbs, a shovel or bulb planter can be used to plant them. Plant the tulips at a depth three times the diameter of the bulb. Make sure to place the pointed tips upwards. For larger areas, you can use a shovel to dig out an area. Plant tulips at a depth equal to three times the bulb’s diameter as well. Make sure the area is leveled. Space the lamps evenly to ensure not only a uniform appearance but also to prevent them from crowding. You can use chicken wire over the lights if you have a squirrel problem. Squirrels treat tulip bulbs like candy and can dig them up before they can rebloom the next year.
You can also help your bulbs in early spring by applying a slow-release fertilizer or organic matter when the leaves are just above the ground. Also be sure to remove spent flowers after they finish blooming in the spring so that energy is directed toward the bulb and not the seed pods (known as deadheads).
Dividing old bulbs, fertilizing appropriately, making sure the bulbs get adequate light, deadheading, and cutting back the foliage only after it wilts will help ensure your tulips re-bloom – saving you money and ensuring you get a lively display every year.
This question was answered by Sierra Williams, Cornell Cooperative Extension, horticulturist, email@example.com.