The tulip tree (Liriodendron tulipifera) is an ornamental tree that produces a breathtaking array of scented flowers in spring. It can reach heights taller than 100 feet, but many gardeners keep it pruned to a more manageable size. Bees love its flowers and people who bake often use tulip tree honey. Its deciduous habit results in beautiful fall foliage in shades of yellow to deep golden. Gardeners in USDA climate zones 5 through 9 will grow this tree successfully.
The tulip tree is a North American native plant, which grows from southern Canada to central Florida. It has been the state tree of Indiana since 1931. Other common names for this tree include yellow poplar, tulip poplar, canoewood and tulipwood. It belongs to the same plant family as the magnolia. The wood of the tulip tree has been used for building the canoes of Native Americans and later log cabins in its native area and it is valued for its presence in forests. It is thought that the young Abraham Lincoln squared a tulip tree log for use as a cabin beam.
The tulip tree can become very tall --- up to 150 feet has been reported in Florida. The spread of its branches can reach 30 to 50 feet. The canopy is symmetrical, without pruning, and the overall shape is bulbous and smooth. The flowers, which bloom in mid-spring, are greenish-yellow, have a pleasing scent and are considered "showy." The tulip tree develops dry, hard brown elongated fruits, which are 1 to 3 inches long. Although the fruit is not considered edible for humans, many birds dine on it. The tulip tree can be messy because its fruit, leaves and falling twigs will litter areas under where this tree grows.
The Liriodendron genus contains only two species, but the tulip tree species contains several varieties. Some of them are called Aureomarginatum, Flashlight, Majestic Beauty, Fastigatum, Arnold, Florida Strain, Integrifolium, Little Volunteer, Mediopictum, Pyramidale and Roothaan. You probably won't be able to find them readily available at commercial nurseries.
How to Grow Tulip Trees
If you have a large yard, plant your tulip tree in a sunny area that has sandy to loamy, well-drained soil. It is drought-tolerant after its root system becomes established. Although you can prune the tulip tree in winter to keep it the size you want, it's not necessary to prune it for it to develop a strong trunk and overall structure. Fertilize in late summer or fall with a plant food that is higher in nitrogen than phosphorus and potassium; for example a fertilizer having an N-P-K ratio of 10-4-6 or 20-5-10 --- regular fertilizing will keep your tree healthy and will make it less susceptible to insects and diseases.
The tulip tree's health is not normally affected by pests, either insects or diseases. However, the Tuliptree aphid and Tuliptree scale insect create a sticky deposit called honeydew, which can result in a sooty black mold on its leaves. Control aphids and scale by first controlling ants, which they "farm" for their honeydew. Also spray your tree with insecticidal soap as soon as you notice aphids. Several diseases, such as cankers and powdery mildew, can affect tulip trees. Keep infected branches pruned to control diseases and always rake fallen leaves to prevent disease from spreading. Dispose of infected plant parts at your landfill instead of in your compost pile.