It’s a common scenario — you planted tulip bulbs in the fall, waited patiently all winter, and nothing came up. Or, there are leaves, but your bulbs didn’t bloom. Or, the leaves were damaged, discolored, stunted, or twisted.
What happened? What can you do? What did you do wrong?
Most times, it’s not your fault. But some problems can be avoided with the right actions.
What are cultural problems?
In horticulture, we use the word “culture” to mean the practices and methods people use in caring for plants. From site selection to planting, to fertilizing and watering, these actions – cultures – can determine a gardening project’s success or failure. Sometimes our cultural practices can invite disease or insect problems.
So let’s look at culture first.
Tulips need to be planted at the proper time, in a proper location, and at the proper depth. Failure to do so can invite a host of problems.
Be Sure Your Bulbs Are Healthy
Buy from a reputable spring bulb grower and inspect the bulbs before you plant them. Throw away any that look withered, are moldy, or feel soft and squishy.
Healthy bulbs are firm, white or beige in a papery jacket and have no cuts, spots, or streaks.
Plant in the Fall
Plant when soil temperatures are below 55°F (12.8°C), but don’t wait too long – you can’t plant bulbs after the soil has frozen. Depending on your horticultural zone, bulbs can be planted from mid-October through November.
Tulips need 6 to 8 hours daily. Check the sun’s path through your garden – full sun might be different in the spring than at planting time.
Constantly wet or mucky soils will cause the bulbs to rot. Site them away from downspouts and low places where water collects. That corner of your garden that never dries out is not the spot for to be planting your bulbs. Water the bulbs after you plant to settle the soil, but they will not need to be watered again.
Most tulips need to be planted 6 to 8 inches deep. Measure with a ruler if you want to be sure. Failure to plant at the proper depth exposes your bulbs to animal pests or the weather’s whims, which will impact flowering.
These steps go a long way to creating a beautiful spring flower garden. Happy plants are healthy plants, and healthy plants are better able to resist diseases. If you want more details about proper tulip planting, check out our comprehensive guide here.
The best way to combat plant diseases is to prevent the disease from happening in the first place. How do we do that?
First, follow the cultural practices listed above. Second, be aware of the problems that could occur and watch for signs of trouble.
Tulip Fire (Botrytis)
Tulip fire is a fungal disease that affects every part of the tulip. Leaves are discolored and twisted and look burnt or scorched. If the flower does emerge, it will also be spotted. The spots get moldy, and eventually, the whole plant rots and collapses.
Botrytis can be on the bulbs you bring home. Buy from a reputable grower and inspect bulbs before planting. Throw away any that have small black spots — this is Botrytis in its infancy.
Once the tulips emerge in the spring, if you see signs of Botrytis, dig up and destroy the bulbs immediately. Do not compost them. Do not plant other tulips in that area for at least three years because the fungus can persist in the soil.
Once a fungal disease takes hold, nothing can be done to cure it. All fungicides are preventative treatments and need to be applied before you see signs of the disease. Unfortunately, fungicides to prevent Botrytis are not available to the home gardener.
Bacterial Soft Rot and Other Rots
Rots can develop when conditions are too wet. First, we see spots on leaves and stems that look wet or water-soaked. Over time these spots grow and become soft and sunken, then mushy, discolored, and stinky. Once rot has set in, there is no cure. Dig up and discard the bulbs.
Rots can be avoided by planting only healthy bulbs and keeping the tulip bed dry.
Tulip breaking virus (TBV) creates striped, broken-patterned flowers. The leaves can also be striped or mottled. Leaves and flowers are at first distorted, and then the plant declines, then dies.
TBV is spread by aphids early in the growing season, before the plant flowers.
No matter how striking the broken patterns and colors, infected tulips should be dug up and destroyed. If you don’t destroy them, aphids will likely spread TBV to neighboring flowers.
Tulips infected with TBV were wildly popular in the 1600’s. Sales and futures of these bulbs skyrocketed creating a phenomenon called Tulipmania.
Today the sale of these infected tulips is prohibited in the U.S. and other countries. Breeders have developed a series called “Rembrandt” that have a broken pattern that are disease-free.
These small, mainly green (but other colors too), soft-bodied, insects hang out on the leaves’ stems and underside. They suck juices out of the plant, causing discoloration. They can also carry TBV (above).
A spring bulb can survive a small aphid invasion, but often cannot survive larger infestations. Keep aphids under control with a blast from a hose, a squirt of insecticidal soap, or friendly ladybugs.
These tiny, tiny arachnids suck juices from leaves. They weave very fine webs, usually in crotches of leaves and stems. The damage they cause creates a white or yellow speckled appearance.
A good way to tell if you have spider mites is to shake the plant’s affected part over a sheet of white paper. Watch for little dots – if they’re moving, they’re spider mites. Control them with a strong blast from your hose (don’t hit the flower). Insecticidal soap works on these guys too, even though they are not insects.
Slugs have fat, soft boneless bodies and leave a slimy trail. They do their damage at night, eating holes in leaves, and sometimes in the flowers. They like moist and cool conditions, so keep the soil dry and free of debris.
Toads eat slugs, so invite these garden friends to your yard. You can buy commercial slug traps or pour a bit of beer into a small container and set in the garden with the lip of the container level with the soil. Slugs are attracted to the beer. They will go into the container and drown.
Squirrels and Chipmunks
These guys can be a problem in the fall. The smell of freshly disturbed soil attracts them and they will dig right where you just planted. If your spring bulb is planted at the proper depth, squirrels and chipmunks generally won’t dig that deep. A piece of screening or bird net over your garden can also deter them; they’ll lose interest after a while.
Rabbits attack in the spring. Rabbits have sharp teeth and they bite on a diagonal. Rabbit damage looks like someone took a pair of garden clippers to your flowering plants – their bite is that precise. Sometimes, they don’t even eat what they’ve bitten. A sure sign they’ve been after your spring bulbs.
You can keep rabbits from damaging your tulips by applying a product like Liquid Fence. It smells really bad — like rotten eggs — but it doesn’t harm the rabbits, it just repels them. If you’ve observed rabbit damage in your yard over the winter, you can be sure they will find your tulips, so begin applications before the tulips emerge. You may need to make several applications of the repellant. Read the product label and follow the directions.
If you have pets, their presence can deter rabbits, but that depends on the rabbits’ boldness. I’ve had rabbits lunch on my flowering plants not three feet away from me while my old dog just watched.
Physical barriers can help. You can surround your spring bulb garden with cylinders of chicken wire, but it’s not a very attractive addition to your floral display.
Deer are browsers and will eat trees, shrubs, hosta, flowering plants, and tulips.
Deer damage is very distinctive. As the bulbs send up their first leaves, deer will grab the leaves with their mouths, pull the bulb up, and munch away. You can tell deer damage by the divots and half-eaten bulbs and leaves and, of course, footprints.
White-tailed deer can clear an 8-foot fence. If you live in an area with a large deer population, you might want to consider fencing your entire garden, not just your tulips. Liquid Fence will work for deer, too or another product you can try is Plantskydd. This non-toxic repellent is better for larger areas. Again, read the label and follow the directions.
Everything Has a Lifespan
Everything has a lifespan, and tulips are no exception.
There are tulip varieties that are bred to return another year, but many are not. Most of them are meant to offer one gorgeous show the spring after you plant them. Then the bulb splits and it could be many years before these little bulbs are big enough to flower again. Even tulips bred to perennialize or naturalize could peter out after a few years.
Don’t feel bad if you unable to create a bloom the second year. To encourage a repeat performance, do the following: When the petals are gone, cut the stem down. This prevents the tulip from using energy to set seed.
Don’t cut the leaves! Let the foliage wither and die in place. This feeds the bulb for next year.
Try to keep the soil dry. This could be hard to do when interplanted with thirsty flowering plants, so make mixed beds with perennials like sedums, daylilies, and ornamental grasses or annuals like moss roses, marigolds, and zinnias.
Knowing these common problems will equip you to be a better tulip planter. So get out there.