Here at Gardening Know How we get lots of questions, and our goal is to provide answers to those inquiries to the best of our knowledge. When it comes to growing bulbs, tulips are at the top of the list. The following article includes the 10 most commonly asked questions about tulip bulbs and their care in the garden.
In general, the best time to plant tulip bulbs is in the fall around the months of October to November in the Northern Hemisphere. If you live in a mild winter area, you could even wait until December. Keep in mind that those residing on the opposite side of the globe (Southern Hemisphere), like Australia, will have different planting times – such as late April to May.
2. Why are there no flowers on my bulbs, just green leaves?
There are a multitude of reasons why your tulips are not bearing flowers:
Lack of Nutrients: Tulips need phosphorus to form flower buds. Conduct a soil test to verify that your soil is phosphorus deficient. Consider fertilizing your tulip bulbs annually with a phosphorus rich fertilizer to provide a much needed boost.
Inadequate Growing Conditions: Were the tulips planted in a location that receives full sun? Is the soil well draining? Were the tulips planted at the right depth (tulips should be planted three times deeper than they are tall)?
Energy-Deprived Bulbs: Resist the urge to mow down the foliage after the tulip flowers are spent. Prematurely cutting down the foliage prevents the leaves from storing enough energy to form the flower bulb. Let the foliage die back naturally instead and snip off any spent tulip blossoms so that energy isn’t diverted to a tulip’s seed producing efforts.
Bad Bulbs: Sometimes the bulbs that we purchase are not healthy. Inspect your bulbs before buying and planting. Were the bulbs you acquired plump and firm? It is recommended when buying a load of bulbs to slice one open and take a peek to see if the flower bud in the center is brown and dried up.
3. Can you replant tulips that have already bloomed?
Assuming you are talking about replanting bulbs that have been forced indoors over the winter, yes, you can – however, you may or may not get another bloom off them because tulips don’t rebound very well after being forced. But, to give yourself the best chance for tulip reblooming success, allow the foliage to die back naturally and store the container in a cool, dry location until spring. When planting, apply some bulb boosting fertilizer to the top of the soil where you planted your bulb.
4. How to take care of potted tulips?
If growing the potted tulips for indoor enjoyment, they will need to be forced (refer to question #8 “How can I force tulip bulbs?”) in order to receive the cold dormant period they require. The care of forced tulips is easy once the foliage emerges. Simply water the tulips when the soil is dry to the touch and keep the plant out of direct light and drafts.
Tulip bulbs planted in containers that are destined for placement outdoors are planted at the same depth as their in-ground outdoor counterparts. Consider layering your bulbs, with 3-4 inches (7.6-10 cm.) of potting soil between each layer, to create visually dynamic arrangements based on tulip height and color. Those in zones 6 or below can store the pot in a cool sheltered area such as a garage or basement. Water the container about once a month and bring it back outside, with a dose of fertilizer, in early spring. Those in zones 7 on up will want to pre-chill their bulbs prior to planting.
5. When should you dig up and divide tulips?
Tulips should only be dug up and divided after their foliage has completely died back, which would make your target any time from mid-summer to mid-fall.
6. How can I store my tulip bulbs until planting?
When digging up tulip bulbs for storage, brush any excess dirt off of the bulbs. Obtain a cardboard box and newspaper. Layer the bulbs in the cardboard box with newspaper sandwiched in between each layer, taking care that the bulbs in each layer do not touch. Store the box in a cool, dry place such as a basement or garage. Inspect the bulbs periodically and toss any that become mushy.
7. How do I keep animal pests from eating my tulips?
Tulip bulbs can be ransacked from below ground by voles or above ground by squirrels, or even deer. While there are many methods proposed for combatting these pests, here are a few tips on protecting your bulbs from rodents:
- Laying and staking down chicken wire over the planting area can be an effective deterrent for our squirrelly friends.
- As for voles, you can try constructing and embedding a makeshift cage into the ground using mesh with half inch holes. Plant your bulbs inside these cages – the bulb’s roots will still have free reign to penetrate through the mesh.
- You can also try lining your bulb holes with sharp textured gravel, which voles do not like burrowing through.
8. How can I force tulip bulbs?
Buy spring tulip bulbs in the fall for the express purposing of forcing. Store them 12-16 weeks in a cool dark place that is 35-45 F. (2-7 C.). After this chilling period, procure a container with good drainage. Fill it with good quality potting soil 3-4 inches (7.6-10 cm.) shy of the container’s top rim. When planting tulip bulbs in containers, the flat side of the bulb should face toward the outside of the pot with the pointy end of the bulb facing up. Bulbs should be spaced at least one inch apart. Fill the container with soil, leaving the very tip of the tulip protruding through the top of the soil. Place the pot in a cool, dark place and water lightly once a week. Once foliage emerges, place the pot in bright indirect light and you should be rewarded with blooms in 2-3 weeks. Tulips can also be forced in water.
9. Do blooming tulips need protection in winter?
Tulips and other bulbs in bloom are more sensitive to frosts and freezes than they are when their buds are in a closed state. And this is really more of a concern for periods of prolonged cold, lasting several days. However, to err on the side of caution, a bed sheet hovered over the plants, supported by stakes, is an ideal way to protect your plants.
10. How and when to fertilize tulip plants?
Fertilize tulips once a year in the fall using a slow release tulip bulb fertilizer with a nutrient ratio of 9-9-6. If you do not want to use or seek out pre-packaged fertilizer, you can concoct your own mix using equal parts blood meal, green sand and bone meal.
We all have questions now and then, whether long-time gardeners or those just starting out. So if you have a gardening question, get a gardening answer. We’re always here to help.