Bulb · Liliaceae
Tulip
Tulipa spp.
Pop the bulbs in come fall, hand them a long cold winter, and tulips light up spring with its boldest color.
Full sun
USDA 3–8
9–24 in · 23–61 cm
Overview
Tulips are part of the lily family, and they got their start in the mountains of central Asia, where cold winters and dry summers shaped the way they grow. Each one's a spring-flowering bulb, sitting on a whole season's worth of energy underground until the weather warms up. That stored-up fuel is exactly why a single bulb can throw up a strong stem and a bright cup of color in just a few weeks of spring.
The one thing tulips ask for is a proper winter. A bulb needs 12 to 16 weeks of cold before it'll flower, so if you're in a mild zone you either chill the bulbs first or just enjoy them for one season. Most modern hybrids fade after a year or two anyway, so a lot of folks plant fresh bulbs every fall and treat them like a happy annual.
And what do you get for it? Plenty. Tulips run 9 to 24 inches (23 to 61 cm) tall and come in just about every color, from a little 6 inch species tulip to a tall Darwin hybrid. Give them full sun and soil that drains well, and they'll hand you the first big show of the year.
Care
The short version: tulips want full sun, fertile soil that drains well, and a bulb tucked 6 to 8 inches (15 to 20 cm) deep in fall. Water it in, don't let the soil get soggy, and let the leaves die back on their own once the blooms are done.
Light
Tulips love full sun, so shoot for 6 or more hours a day to power a good bloom and top the bulb back up. They'll take a bit of partial sun, but too much shade? That leaves you with weak flowers, or none at all.
Water
Give the bulbs a good soak when you plant them, then pretty much leave them be. Tulips can't stand soggy soil, which rots the bulb, so keep them on the dry side once the leaves fade and the bulb goes to sleep.
Soil
Plant them in rich, fertile soil that drains well, and you're most of the way there. Drainage really is the big one here, because a bulb sitting in wet ground will rot long before it ever gets to bloom.
Humidity
Tulips don't care much about the air around them, so there's no number to worry about. What matters way more is good drainage and airflow, since damp, crowded spots are exactly where tulip fire and bulb rot like to start.
Feeding
Feed them a balanced slow-release fertilizer, something like a 5-10-5, at planting and again once the flowers fade. Bone meal? Skip it. It's not needed and it just invites diggers, so a plain balanced feed is the way to go.
Pruning
Snip off the spent flowers so the bulb isn't wasting energy making seed. Then let the foliage hang around until it yellows and browns on its own, usually late June into July, because cutting it early leaves the bulb hungry.
Repotting
Every few years, once the foliage has died back, dig up a crowded clump and split it, then replant the bulbs at the right depth. You'll know it's time when you see smaller flowers and fewer blooms, or bulbs starting to poke up toward the surface.
Overwintering
Tulips are hardy in zones 3 through 8, so they happily ride out winter right in the ground and soak up the cold they need. In zone 9 and warmer, though, you'll want to pre-chill the bulbs for 12 to 16 weeks or just replant fresh ones each year.
Size & spacing
Depending on the type, tulips stand 9 to 24 inches (23 to 61 cm) tall. Set the bulbs 3 to 6 inches (8 to 15 cm) apart and 6 to 8 inches (15 to 20 cm) deep, with the pointed end facing up.
When to plant
Here's the fun twist: tulips run on a backwards schedule compared to most plants. Plant the bulbs in fall before the ground freezes, let them wait out a long cold winter, and the flowers show up from April into late May.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Plant: September–November (fall before ground freezes; October ideal)March–May
- Bloom: April–May (early April to late May by division)October–November
Hardiness
USDA hardiness zones: 3–8
Temperature: down to -40°C
Troubleshooting
Most tulip headaches either start underground or come strolling in on four legs. Think a rotting bulb, a hungry deer, or a hybrid that's just run out of gas. Find what matches below, and step in early before it works its way through the bed.
Scorched, twisted leaves with a fuzzy gray mold
That's tulip fire, a fungus called Botrytis tulipae, and it really takes off in damp, cool, overcast weather. Pull and destroy anything showing it, and don't ever plant a bulb that's got little black pinhead specks on its husk. Move the bed to fresh ground and the disease has nowhere left to hide.
Fix:
- Remove and destroy infected plants
- Apply fungicide as leaves emerge
- Discard damaged or spotted bulbs
Soft, smelly bulbs that barely grow or don't at all
This one's bulb rot, and nine times out of ten it's wet, poorly drained soil turning the bulb to mush. Dig one up and check; if it feels soft and looks discolored, toss it. Sort the drainage out before you replant, or that next bulb's just going to rot all over again.
Fix:
- Discard rotted bulbs
- Improve drainage before replanting
Fresh holes and missing bulbs right after planting
That'll be squirrels, chipmunks, voles, and mice, who love digging up fresh bulbs, and bone meal in the hole only rings the dinner bell faster. Leave the bone meal out and lay some hardware cloth or chicken wire over the bed. A simple barrier beats any repellent, hands down.
Fix:
- Cover beds with hardware cloth/chicken wire
- Skip bone meal
Streaky petals and mottled, stunted leaves
Weird streaks that aren't part of the variety usually point to tulip breaking virus, which aphids carry from plant to plant. There's no fixing it, so dig up and destroy anything infected, bulb and all. Keep the aphids in check and you'll stop the virus before it spreads through the bed.
Fix:
- Dig and destroy infected plants and bulbs
- Control aphids
Loads of leaves but hardly any flowers
These are what gardeners call blind tulips, and most modern cultivars end up here after 3 to 5 years. Cutting the leaves before they die back starves the bulb, and so does too little sun. Just let the foliage yellow on its own, plant in full sun, and drop in fresh bulbs when an old clump calls it quits.
Fix:
- Replace exhausted bulbs with fresh ones
- Let foliage die naturally
- Site in full sun
Shoots, buds, and flowers bitten off in spring
To deer, tulips are basically a spring buffet, and rabbits will nibble them too. Repellents help a little, but a truly hungry deer walks right on past. A real fence is the only thing you can count on, so if the bed's out in the open, expect a few chewed stems.
Fix:
- Fence or exclude with wire
- Apply repellents (less effective)
Twisted shoots with aphids on the bulbs and leaf bases
The tulip aphid likes to pile up under leaf sheaths, at the base of the plant, and even on bulbs you've got in storage. Those pale-green bugs spread the breaking virus, so don't sit on it. Dunk any infested bulbs in insecticidal soap, and treat growing plants with soap too, or something stronger if they just won't quit.
Fix:
- Immerse infested bulbs in insecticidal soap
- Treat plants with insecticidal soap, pyrethroid or systemic
Fewer, smaller blooms year after year
Most modern hybrids fade after that first year, and a warm climate that can't give them enough winter chill only makes it worse. So treat hybrids like annuals and replant, or go with species and Darwin hybrid types that bounce back better. In mild zones, give the bulbs a pre-chill before they go in.
Fix:
- Replant fresh bulbs annually
- Choose species or Darwin hybrid types
- Pre-chill bulbs in warm zones
Toxicity
Here's the thing: every part of a tulip is toxic, and the bulb is by far the worst. It's loaded with irritant compounds called tulipalin A and B, and they upset the stomach in pets and people alike. So keep your bulbs, planted or stored, away from animals and kids, and throw on some gloves when you handle them.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds · People
Cats Moderate
You'll probably see drooling, vomiting, and diarrhea, often with your cat acting low and dull. The bulb's the worst part, so keep both stored and planted bulbs where a cat can't get at them.
Dogs Moderate
Look for drooling, vomiting, and diarrhea after a dog's dug up or chewed a bulb. And if a small dog swallows a whole one, it can actually block the gut, so that's worth watching.
Horses Moderate
The bulb tends to bring on a stomach ache and a dull, down mood. Keep tulip beds and any stored bulbs well away from where horses graze.
Rabbits Toxic
Tulips carry irritant compounds that rabbits should never eat, and the bulb's the most dangerous bit of all. Fence the plants off and keep the bulbs nowhere near the hutch.
Livestock Moderate
Cattle, goats, and sheep can react to the bulbs and foliage with drooling, vomiting, and diarrhea, and a big helping might even bring on heart and breathing trouble.
Birds Toxic
The bulbs and foliage are toxic to birds, plain and simple. Keep poultry and pet birds away from tulip beds and any bulbs you've got stored.
People Caution
No part of a tulip is safe to eat, and every so often the bulbs get mistaken for onions or shallots. Eat one and you're in for vomiting and diarrhea, and handling bulbs bare-handed can leave a rash, so wear gloves.
Bulb is most toxic; handling bulbs can cause 'tulip fingers' contact dermatitis
Helpline numbers
United States
ASPCA Animal Poison Control: (888) 426-4435 (fee applies)
Poison Control: (800) 222-1222
Canada
Poison Centres: 1-844-764-7669
Varieties
There are 15 official divisions of tulips, but honestly only a few show up in most gardens. Here are the ones worth knowing by name.
Darwin hybrid
This class puts out big, sturdy blooms in mid-spring, hangs on the longest, and comes back better than the other hybrids.
Triumph
Triumph's the largest class, and it gives you those classic cup-shaped single flowers in mid-spring in just about any color you'd want.
Parrot
You'll spot Parrot tulips right away thanks to their fringed, twisted, and feathered petals.
Species/botanical (e.g. Tulipa tarda)
These low-growing tulips live the longest, spread around on their own, and open white flowers with a little yellow eye.
Tulipa batalinii
This species tulip carries soft-yellow single flowers on 6 to 10 inch stems in April.
How to propagate
Tulips quietly multiply underground all on their own, and you can nudge things along by splitting the bulbs. Fancy growing them from seed? You can, but you'll need real patience.
Bulbs & cormsModerate
Lift and separate offsets when dormant in summer · 1-3 years to flowering size
When a clump gets crowded, dig it up while it's resting dormant in summer and pull the little daughter bulbs off the parent. Most are too small to flower that first year, so just replant them and give them time. Figure on 1 to 3 years before they're big enough to bloom.
SeedDemanding
Sow ripe seed; mainly for species tulips · 4-7 years to first bloom
Growing tulips from seed is slow going, and it really only works for species types. Sow the ripe seed and wait, because a seedling takes 4 to 7 years to bloom. And hybrids won't come true from seed, so whatever pops up won't match the parent.
Myths
Tulips come back bigger and better every year.
Not really. Most modern hybrids fade after 1 to 3 years, which is why plenty of gardeners just plant them as annuals and start over. Species tulips are the ones that actually perennialize.
Plant the bulbs as deep as you possibly can.
Go for about 2 to 3 times the height of the bulb instead, which lands around 6 to 8 inches. Bury it too deep and the bulb wears itself out just getting back up to the surface.
Tie, braid, or cut the leaves right after bloom to tidy up.
Leave the leaves be until they die back on their own and turn brown. Cut that green foliage early and you starve the bulb, leaving you with blind, flowerless plants next spring.
You've got to use bone meal when you plant bulbs.
Most soils already have plenty of phosphorus, so bone meal rarely helps, and it leads squirrels and other diggers right to the bed. A balanced slow-release feed just works better.
A late spring snow will kill tulips that are already up.
Nope. Tulip foliage shrugs off frost and light snow, and that snow even acts like a blanket. It takes a hard, bare freeze below the mid-20s°F (about minus 4°C) to do any real harm.
Sources
- ASPCA Animal Poison Control
- Iowa State University Extension
- Iowa State University Extension
- University of Illinois IPM (Report on Plant Disease 609)
- NIH/NCBI PubMed Central
- Missouri Botanical Garden Plant Finder
- Royal Horticultural Society
- NC State Extension
- Iowa State University Extension
- University of New Hampshire Extension
- University of Georgia Extension
- Iowa State University Extension