Origin and Distribution
Under no circumstances should you confuse the tulip tree with the sometimes also called tulip magnolia (Magnolia soulangeana). Both species belong to the magnolia family (Magnoliaceae) and are therefore closely related to one another, but they look only slightly alike.
- How to care for a tulip tree - tips and tricks
- Do I have to cut my tulip tree regularly?
- When does a tulip tree bloom?
The tulip tree (bot. Liriodendron tulipifera) is native to eastern North America, where it is widespread between the Great Lakes on the border with Canada and the Appalachians to northern Florida. Here, the largest deciduous tree in North America thrives primarily on moist or occasionally flooded soils in floodplains and valleys.
In addition to the American subspecies, the Chinese tulip tree (Liriodendron chinense) is another representative of the tulip trees (Liriodendron) in China and Vietnam. Incidentally, both tulip and closely related magnolia trees can already be identified for a period of at least 100 million years, with both species also thriving on other parts of the world - for example in Europe - in earlier geological ages.
The tulip tree came to Europe from North America very early: the first specimens were planted in German and other Central European parks as early as the 17th century, some of which can still be admired today.
Since the wild species of the tulip tree reaches enormous heights, it should only be planted in large gardens or parks. Here it is particularly suitable for a stand-alone position, but also looks interesting and imposing in parks as a group or avenue planting. In the meantime, there are some significantly smaller cultivars such as the two varieties 'Fastigiatum' (15 to 18 meters height) and 'Aureomarginata' (12 to 15 meters height) for the home garden. Since these variants have also been refined, they bloom a few years earlier than the wild form - this often only develops its fascinating bloom after the age of 20.
In the USA and Canada, the tulip tree is one of the most important useful trees. Its light, finely grained wood - which is not without reason also known as "whitewood" - is used in furniture production and is used for doors and window frames, veneers and cladding, but also processed into toys, musical instruments and coffins. The tulip tree is also a valuable raw material in pulp and paper production.
In the garden, the blooming tulip tree serves as a valuable, extremely nectar-rich bee pasture.
Appearance and stature
At 41 meters high, it is one of the largest (and at around 450 years probably also the oldest) tulip tree in America is located in New York City in the borough of Queens. He is nicknamed “Queens Giant”, although there are some other impressive members of his genus around the world. One of them is located in the botanical garden of the city of Marburg and is also almost 40 meters high.
Tulip trees grow very quickly at around 30 to 70 centimeters per year, with the pyramidal crown also increasing by around 20 centimeters each year. Although this remains quite narrow, it can still be between 15 and 20 meters wide for 25 to 35 meter high specimens. The main branches show a steep upward growth. The trunk grows straight up, looks rather slim with a maximum diameter of 150 centimeters and thickens strongly near the ground, which gives the species, which often grows in flooded areas, greater stability. The longitudinally cracked, light gray bark is also characteristic.
The tulip tree is a deciduous, deciduous tree whose fresh green, alternating leaves turn bright golden yellow in autumn. The shape of the leaves is unmistakable, which is why the tulip trees can be easily identified by the knowledgeable: They are divided into four pointed, protruding side lobes. In addition, the leaves are quite large: the actual leaf is up to 15 centimeters long and up to 20 centimeters wide, with the shape being almost rectangular. There is also a petiole about ten centimeters long.
Flowering and flowering period
Depending on the location and the weather, tulip trees open their unique flowers between April and May or May and June. The bisexual yellow-orange flowers are reminiscent of tulip blossoms in shape, are initially cup-shaped, later bell-shaped. Up to five centimeters long, thick and fleshy stamens protrude from the center of the flower. The flowers of the tulip tree are very nectar-rich and are therefore popular with bees, bumblebees and other insects.
Unless it is a tulip tree that has been propagated through grafting, you have to wait a long time for the first bloom: Specimens grown from seeds in particular wait at least 15 to 20 years with the first bloom.
After pollination, the tulip tree develops up to seven centimeters long, spindle-like fruits that are vaguely reminiscent of coniferous cones. They are winged and contain about one or two seeds.
All parts of the tulip tree are considered to be slightly poisonous to both humans and animals. Both leaves and flowers are therefore unsuitable for consumption. Bark and wood, in which the alkaloid glaucine can be found, have a particularly high proportion of toxins. The sap, in turn, can cause allergic reactions on contact, for example by pruning.
Which location is suitable?
The tulip tree feels most comfortable in a sunny and sheltered location. This is especially important because older specimens in particular have a tendency to wind break. The tree also grows in partial shade, but much more slowly there. In addition, the tulip tree will not grow that big in a darker place in the garden.
The optimal substrate for the tulip tree is:
- nutrient-rich and humus
- loose and permeable
- as loamy as possible
- fresh to moist
- acidic to slightly alkaline
Basically, the species also thrives on sandy, dry soils, but in this case grows much more slowly. On the other hand, the floor should definitely be free of lime.
A permanent pot culture is not recommended due to the rapid growth and the expected size. The species is also not suitable as a bonsai.
Plant the tulip tree correctly
Plant the tulip tree in its intended location as follows:
- Place the tree in a bucket of water so that the roots can soak up.
- Dig a planting hole that is about twice as large and as wide as the root system.
- Slightly loosen the soil on the side walls and the perforated base.
- Sludge the planting hole well.
- Mix the excavated material with compost and horn shavings, (€ 6.39 on Amazon *) if too lean / sandy.
- Plant the tree, but not too deep.
- Fill in the soil, gently tread it down.
- Water the tree.
- Spread a layer of bark mulch or leaf compost.
In the following weeks you should water the freshly transplanted tree more.
What is the best time to plant?
Basically, you can plant the tulip tree in the garden at any time between October and March, provided the weather is mild and the ground is frost-free. However, since the species has very sensitive roots that can be damaged by planting in autumn or winter, spring is recommended as the ideal planting time - as late as possible and in any case after the ice saints.
The correct planting distance
Planting in a single position is ideal. You should keep a minimum distance of five meters (better more) to other trees.
As a heart root, you can safely underplant the tulip tree with ground cover as well as with small ornamental shrubs or perennials, as long as these withstand strong root pressure and naturally require little water and nutrients. In return, the underplanting has the advantage that it practically acts like a water reservoir and prevents the soil from drying out. With age, Liriodendron tulipifera forms a hemispherical root foundation, which rises up and the tree from the earth and thus ensures more stability. At this point, of course, underplanting is no longer possible, but it will take several decades to centuries.
Well-suited for underplanting are, for example, the spring memorial (Omphalodes verna), holy herb (Santolina chamaecyparissus), Japanese forest grass (Hakonechloa macra), cork's beak (Geranium magnificum), golden fox (Lysimachia punctata) or lady's mantle (Alchemilla mollis). Since tulip trees are rather slender and have a narrow crown, the space under the wood is often very light.
Watering the tulip tree
Freshly planted tulip trees should be watered regularly to make them easier to grow. But even with older specimens, timely watering is important in persistent drought, as the trees quickly shed their leaves when there is a lack of water. However, the tulip tree can usually cope with a short-term lack of water. Incidentally, the splendid autumn color is only developed if there is sufficient water supply, which is why you should still use the watering can in late summer if necessary. Although the tulip tree needs a lot of water, like most plants, it does not tolerate waterlogging. Permanently wet floors should therefore be avoided if possible.
Fertilize the tulip tree properly
In spring and again in early summer you should provide the tulip tree with plenty of ripe compost and a generous handful of horn shavings (€ 6.39 at Amazon *). The species also gets very good fertilization with rhododendron fertilizer, which acidifies the soil and kills two birds with one stone: the heavily sapping tulip tree receives the necessary nutrients while at the same time providing an acidic feel-good environment. In principle, fertilization is only carried out between April and July, after which the nutrient application must be stopped. The reason for this is that the new shoots have to mature in good time before winter and no further shoots are stimulated to grow - these remain too soft and would freeze away in frosty temperatures.
Cut the tulip tree correctly
Like the magnolias, the tulip tree does not tolerate regular pruning, which is why it is better not to touch it with scissors. In addition, any training or correction incisions are not necessary, the species develops an appealing crown structure on its own. Only young trees can still be corrected in their growth by pruning, whereas older trees can no longer. It also makes sense to remove dead or diseased material, which you should do in early spring if possible.
Propagate the tulip tree
Typically, tulip trees are propagated by seeds or, in the case of cultivated forms, by grafting to the wild form. But you can also cut cuttings in spring and use them to grow new trees. This is how cuttings propagate:
- In April or May, cut head cuttings about four to six inches.
- If necessary remove leaves except for two leaves.
- Cut large leaves in half.
- Slightly bevel the cut surface, dip in rooting powder.
- Now put the cuttings in a small pot with growing substrate (9.05 € at Amazon *).
- Pour well with lime-free water.
- Cover the pot with a cut-off PET bottle or foil.
- Place light and warm at 20 to 26 ° C, water and ventilate regularly.
Be patient with your young cuttings: they usually take a long time to develop their own roots. As long as the cutting looks healthy and the soil does not go moldy, everything is good and you don’t need to throw in the towel yet.
How do I transplant properly?
Tulip trees should, if possible, not be moved if they have been in their location for several years and are well established there. The trees do not tolerate transplanting because their extensive and sensitive root network is inevitably damaged. In any case, large specimens can only be removed with heavy equipment, which is associated with considerable effort and high costs.
In contrast, you can transplant young tulip trees that have been in place for a maximum of three or four years and have not yet grown too high in a relatively straightforward manner. But here too, this measure needs to be well prepared by digging a spade-deep trench around the tree in the fall and filling it with compost. This means that the roots develop more compactly by the following spring, so that the loss is not too drastic. Move the tree in late spring and be sure to prune it back so that the balance between the aboveground and underground plant matter is preserved.
Diseases and pests
Diseases and pests rarely occur in the tulip tree - as in all magnolia plants. The only problem that can be problematic is keeping it too wet, which manifests itself as rot after a while. To prevent this, pay attention to a species-appropriate location, a loose and well-drained subsoil, in which you can install a drainage if necessary, as well as sufficient planting distance.
Sometimes the tulip tree develops brown leaf spots, which can have various causes. Often they indicate a lack of water, but can also be traced back to saline soil - for example as a result of over-fertilization. A rare but not impossible reason is leaf blotch disease, which can usually be managed well with a copper sulfate solution.
Since the tulip tree is sufficiently hardy and frost hardy here, too, special wintering measures are not necessary. Only young trees can be provided with a light protection if it gets very cold.
Since the roots of the tulip tree run close to the surface, you should refrain from deep-rooted underplanting or mechanical processing of the tree disc. This could irreparably damage the roots.
Species and varieties
The genus of the tulip trees (Liriodendron) comprises only two species, both of which can be cultivated as ornamental trees in the home garden. While the American tulip tree in its original form (Liriodendron tulipifera) is only suitable for very large gardens or parks due to its size, the Chinese tulip tree remains smaller with a maximum growth height of up to 17 to 20 meters in the Central European climate. The Asian variant is also hardy here, but branches and twigs can freeze back in severe frost.
In addition, there are two cultivars of the American tulip tree that remain significantly smaller than the wild form:
- Columned tulip tree 'Fastigiatum': Growth height up to approx. 15 meters, very narrow growth
- 'Aureomarginata': fresh green leaves with a yellow-green margin, about 12 to 15 meters high