The tulip tree, Liriodendron tulipifera, also commonly known as the tulip poplar or yellow poplar, is not a tulip or a poplar. It is actually a member of the Magnolia family (Magnoliaceae). These are tall, straight trees with attractive foliage and large, showy flowers that attract hummingbirds and pollinators.
Tulip trees are North American native species that typically grow in rich, moist forests. As a landscaping plant, they make excellent shade, wildlife, and landscaping trees for larger yards. They are adaptable and grow in almost any location with full sun, rich, moist soil, and plenty of available space.
One of the most unique features is their large, showy flowers. While growing high in the forest canopy, you may not even notice the flowers until they fall to the ground. If you spot them while they’re blooming, you easily appreciate their eye-catching orange, yellow, and greenish-white petals.
If growing a tulip tree sounds appealing to you, let’s dig a little deeper into these beautiful plants and how to help them thrive in your landscape.
Plant Overview
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Natural History
Tulip trees are valuable for timber production.
Tulip trees are native to eastern Canada and south into the eastern United States, from Texas east to Florida. They grow naturally in rich, moist forests and mixed woodlands.
The tulip tree genus Liriodendron has just two species. One is native to North America, while the other is native to China. There is also a hybrid between these two species. If you want to grow a tulip tree in North America, however, choose the native variety. There are also some tulip tree cultivars you can try if you’re looking for something a bit different.
This is an important hardwood tree for timber production. Wood from the tulip tree is used to make furniture, plywood, veneer, and paper pulp. Historically, its wood and bark have been used to make useful items such as baskets and canoes.
Characteristics
Mature trees feature tall, straight trunks, smooth gray bark, and distinctive tulip-like flowers.
Tulip trees grow 60 to 90 feet tall, sometimes even taller, and 30 to 60 feet wide. They have a long, straight trunk. The trunks are typically very straight and even. The bark of young trees is smooth and light gray, while older trees develop deeply furrowed light gray and grayish-white bark.
Blooms appear in late spring. The flowers are tulip-like, giving rise to the common name tulip tree. The flowers have large, showy, pale greenish-yellow petals with a bright orange band around the center. The center of each flower has a prominent cone-like projection surrounded by many pollen-bearing stamens.
These are deciduous trees with attractive leaves. The leaves are large, simple, and somewhat square-shaped, with symmetrical broad points along each side. The leaves turn a very showy bright yellow color in the autumn, making these desirable trees for fall foliage displays.
Propagation
The easiest way for a gardener to acquire a new tulip poplar is to purchase a young tree from a nursery or garden center. If you have access to a mature tulip tree, try collecting a dry seedhead in the fall or winter and start your own young tree from seed.
Seed
Gather fallen, dry tulip poplar seedheads in fall or winter, then sow and protect for spring sprouting.
Collect fully dry seedheads that have freshly fallen from a mature tulip poplar tree. The seedheads typically start dropping their seeds and cone-like clusters of seeds in the fall, continuing into the winter months.
If you have access to seeds, allow them to overwinter outside, and they will readily sprout in the spring. Simply directly sow a few seeds where you want a tulip tree to grow and protect them with a critter cage so the squirrels won’t dig them up before they sprout. In the spring, as the weather warms, small tulip seedlings emerge on their own. If you have more than one sprout, thin all but the healthiest-looking plant and allow that one to grow to maturity.
Transplanting
Plant your young tree in early spring or late fall to a prepared location.
If you purchase a young tree at a garden center or nursery, you eventually need to transplant it into a permanent location. The best time to transplant your tree is early spring before it has broken dormancy for the season. Late fall is another good season for transplanting. Ideally, choose a cool and overcast day to transplant.
Identify the permanent location where you’d like your tree to grow. Dig a hole slightly larger than the pot it’s currently in. Carefully remove the tree from the pot and set it in the hole. If the tree is rootbound in the pot, widen the hole and spread out the roots a bit. Refill the hole around the roots with fresh soil and tamp down the soil around the tree.
After transplanting, water your new tree well, allowing the water to soak deeply so the roots get thoroughly wet. This deep watering-in helps your tree recover from transplant shock. Keep the tree well-watered for the first few months so the roots become well-established in this new location.
How to Grow
In desirable conditions, these trees grow rapidly yet require little maintenance to keep them going. Pay attention especially to your soil moisture levels. These trees thrive in consistently moist soils and will not do well in dry, sandy soils.
Sunlight
Tulip trees thrive in full sun, requiring 6-8 hours of direct sunlight daily.
Provide a full-sun location with at least six to eight hours of direct sunlight each day. Young trees grow well as an understory tree, but they must have an available canopy gap of sunlight above to fit into.
Water
Young trees may need extra watering during times of drought.
Tulip trees need moist soil. Consistent medium-moisture soil is best. Young trees require some supplemental watering during periods of drought. Mature trees are fairly drought-tolerant because they have established a broad root system.
Soil
Grow in organically rich, well-drained, slightly acidic soil.
Plant your tulip tree with organically rich, well-drained soil. These trees perform well in slightly acidic soil and tolerate periodically wet soil conditions. That being said, do not leave them in standing water for long.
Climate and temperature
Grow Tulip poplars in USDA Zones 4-9.
Tulip trees thrive in cool to moderate climates and are hardy in USDA Plant Hardiness Zones 4 to 9. These trees tolerate warm temperatures, frost, and humid climates. They will not perform as well in hot, arid climates or extreme cold.
Fertilizing
Wild trees don’t need extra fertilization, but mulching with biodegradable materials enhances soil nutrition and moisture.
Trees growing in natural conditions do not require extra fertilization. You can, however, boost your tree’s performance by mulching around the base with a layer of biodegradable compost.
Use partially decomposed leaf mulch, bark mulch, or wheat straw, all of which break down and add nutrients to the soil as well as help maintain soil moisture levels.
Maintenance
Pruning is only necessary to remove damaged or diseased growth.
Tulip trees are low-maintenance. They do not require regular pruning or trimming unless young trees suffer from storm damage, such as broken branches.
Pull weeds around young trees because aggressive, weedy growth easily outcompetes a young tree. While mowing or using a string trimmer around your trees, be careful not to damage the trunk with your strings and blades.
Garden Design
Plant in a spacious, sunny area at least 60 feet away from structures.
Provide a large sunny space to grow. Make sure your tree is at least 60 feet away from your house to keep leaves and flower debris off your roof and out of your gutters. If you have a large yard, plant a tulip tree as a central focal point, intersperse it with some other hardwood trees, or plant it at a back edge where a large tree might not be intrusive into your other landscaping projects.
Use a tulip tree in a large, natural woodland setting. Plant it alongside other deciduous or evergreen trees, such as oaks, maples, or pines, as long as they all need the same basic environmental conditions.
As a single specimen tree, grow your tulip tree in a large sunny area. Start planning a shade garden in the vicinity of your tree and grow some annuals or perennials that thrive in partial sun conditions.
Wildlife Value
Tulip trees enhance wildlife-friendly landscapes, attracting birds and butterflies while providing diverse habitat.
This is a great plant to add to your wildlife-friendly landscape. The large flowers attract birds, including hummingbirds, as well as many insect pollinators that are active in the springtime. In addition, the trees provide structural diversity in the landscape and habitat for foraging, nesting, and roosting birds, small mammals, and beneficial insects.
Tulip trees are also a larval host plant of the eastern tiger swallowtail butterfly, the spicebush swallowtail, and the viceroy butterfly. Squirrels, deer, and some birds eat parts of the flowers and flower buds in the springtime. In addition, deer and squirrels feed on the seeds in the fall and winter.
Common Problems
You may see an occasional insect infestation or fungal infection, but these trees are generally trouble-free. Be on the lookout for these potential problems.
Aphids
Common pests, aphids feed on the sugars of tender new growth.
Aphid species are extremely common insect pests. They are small, soft-bodied, and typically green, gray, or pink. Aphids use their piercing mouthparts to suck the juices from the leaves and stems of a plant. As they feed, they leave behind a sticky honeydew substance that attracts both ants and aids the growth of mold.
If your tulip tree has aphids, however, you probably won’t notice because they will be high up in the branches. If you see an unnatural yellowing of leaves in the middle of the growing season, it’s possible you have some insect pests like aphids, but there isn’t much you can do about them with such a large tree. Hose down areas you can reach to rip them off the tree.
Mildew
Fungal infections like mildew usually strike in warm climates.
Mildews most likely to occur in warm and humid climates. Fungal infections like this most commonly occur on the leaves of a plant, causing patches of gray or white on the foliage. In a tree as large as a mature tulip tree, it’s quite possible that you would never notice mildew unless the leaves drop prematurely and you see mildew spots on the fallen leaves.
Your best course of action to prevent mildew is simply to grow your trees in a well-ventilated area in full sun. Most cases of mildew on trees are unsightly but won’t cause long-term damage.
Verticillium wilt
As a soil-borne fungus, verticillium wilt causes wilting, yellowing, and eventual death in affected trees.
This kind of wilt is a fungus that affects a wide variety of different plants. It is typically spread either through infected soil or wind-blown spores. Symptoms in trees include a sudden wilting and yellowing of the foliage, followed by browning of damaged foliage. Infected trees may then fail to develop leaves the following spring and eventually die.
If you catch symptoms promptly on a young tree, prune off the infected branches. Older infected trees that have died should be removed to prevent further spread of the fungus. Do not burn logs of infected trees, and don’t use them in your garden or compost pile. Send them to the municipal landfill.
Frequently Asked Questions
The tallest known specimen of tulip poplar is in the Great Smoky Mountains National Park in North Carolina. This tree is located in old growth forest and measures over 191 feet tall. The tulip tree you grow in your own yard is unlikely to get this large!
They are fast-growing trees, but you’ll still need to wait a while to appreciate their shade. A young, healthy tulip tree planted in ideal conditions, with full sun and rich, moist soil, can grow two or three feet per year. As trees get older, their growth rate eventually slows down until they reach their maximum height of 90 feet or more.
If you live in an area with browsing deer and other herbivores, you will be happy to know that they are not an herbivore favorite. Young trees, where the leaves and buds are still low and accessible, might be nibbled by deer, but mammals much prefer to eat something else. As the trees soon grow larger, the tasty parts will quickly be out of reach of deer.
Final Thoughts
If you live in eastern North America, a tulip tree can be a great landscaping plant. These trees are large, tall, long-lived, easy to grow, and low-maintenance. They are also showy shade trees with beautiful spring flowers and very attractive fall foliage. Tulip trees attract birds, pollinators, and other wildlife, creating a natural, healthy, and thriving ecosystem. If you have a large sunny location with moist soil, perhaps a tulip tree would be a welcome addition to your yard!
