The blue bell tree is an imposing sight with only few demands on its care. Provided there is enough space in the garden.
The blue bell tree (Paulownia tomentosa) is a real feast for the eyes. The blue tree blossom is extremely rare, so the lamiaceae from Asia will inevitably attract attention. To ensure that the emperor tree lives up to its name, grows luxuriantly and is in full bloom, the following care instructions should be observed.
Profile
| Bluebell tree (Paulownia tomentosa) | |
|---|---|
| Growth Speed: | 40 - 50 cm a year |
| Growth: | 800 - 1,500 cm |
| Growth: | 800 - 1,000 cm |
| Root system: | Deep Roots |
| Location: | Sun |
| Floor: | Moderately dry to fresh, well-drained garden soil |
Water the bluebell tree properly
The water requirement of the blue bell tree is above average. Nevertheless, mature trees only need to be watered in extremely dry and hot summers. The plant largely supplies itself with moisture via its widely branched root system.
Young plants cannot penetrate deeper layers of the earth with their roots and should therefore be watered regularly. The soil should not dry out, but waterlogging should be avoided in any case. The trees cannot stand it when the moisture builds up in the ground. The roots are attacked, which weakens the Emperor Tree and eventually kills it.
Tip: Drainage makes the substrate more permeable and protects against waterlogging.
If bluebell trees are kept in pots, watering must not be neglected either. The substrate is limited and with it the absorption of liquid and nutrients. Regular watering is necessary in any case, regardless of the age of the plant. Here, too, drainage is advisable, because the risk of waterlogging is far higher with potted plants than with plants that are planted outdoorsbecome.
Coming soon:
- Water young plants regularly
- Water potted plants regularly
- Only water adult plants outdoors in hot summers
- Earth must not dry out
- Avoid waterlogging
Fertilize the bluebell tree properly
Bluebell trees prefer nutrient-rich soil. The substrate can already be upgraded during planting by adding compost. The application of fertilizer should be repeated every spring.
Tip: The occasional application of lawn clippings provides the emperor tree with additional nutrients.
Commercial liquid fertilizers can be saved. On the other hand, watering with nettle manure during the growth period is a good way to strengthen the plants. To do this, fresh nettle leaves are soaked in water for several days. The brew is then strained and added to the irrigation water.
Warning: From August the Kaiserbaum will no longer be fertilized. The fresh shoots would then no longer ripen and would freeze to death if there was a frost.
Coming soon:- Mix the compost into the substrate every spring
- Put lawn clippings on the substrate occasionally
- Use nettle manure as a tonic
Keeping self-seeding under control
Caring for the bluebell tree also includes controlling its spread. The trees prefer to seed themselves and are therefore classified as invasive plants. The neighboring plants run the risk of being literally squeezed out by the emperor tree.
If you fail to remove the seeds from the tree in time, you will have to get rid of the young plants on the lawn and in the beds. The same probably applies to the residents of the neighboring properties.
If you want to avoid this amount of work, but still don't want to do without a blue bell tree, "Nordmax21" offers the solution. A Bonn company breeds this hybrid of the blue bell tree. The plants are well adapted to the German climate, grow quickly and are less sensitive to frost. Arguably the most useful innovation of this breed is the fact that the trees are no longer capable of self-propagation through seed.
Pruning the Bluebell Tree Properly
The bluebell tree is growing very fast and it will be impossible to avoid using the scissors every now and then. Pruning measures can be carried out both in autumn and in spring.
Tip: From May the bluebell tree should no longer be pruned. In late summer, the plants lay the buds for flowering the following year.
If the bluebell tree is pruned, all branches that have grown too dense and negatively affect the shape of the treetop are removed. It is also important to remove dried, diseased or dead branches.
Tip: Pruning improves plant growth. New shoots form very quickly at the cutting points.
It can quickly happen that the crown of the tree has simply become too big. The bluebell tree can already gain about two meters in height in the first year. In this case, a radical cut must be carried out. The upper shoots are shortened to a length of one to two centimetres.
If there was frost damage, pruning is also necessary. This should be done before sprouting. However, late frosts should no longer be expected.
Overview of important care tips
| Care Measure | Explanation |
| Casting | Young plants are watered regularly. Potted plants also need regular water. Mature outdoor plants provide themselves with moisture and nutrients through their roots. The soil must not dry out, and waterlogging should also be avoided. |
| Fertilize | Natural fertilizers are used for fertilization. Compost should be added to the substrate every year. Lawn clippings and nettle manure also strengthen the plant. |
| Cut | Due to the fast and persistent growth, pruning measures are essential. The tree should be pruned regularly. A radical cut is recommended about every two years. |
Detecting and combating diseases and pests
The blue bell tree is robust and is rarely visited by diseases or pests. A unique position is to be ensured right from the planting stage. The tree can then develop optimally and is less susceptible to disease and pest infestation.
Tip: Bluebell trees secrete mucilage that attracts ants. The insects protect the emperor tree from predators.
Every now and then fungus can occur. The fungus species Phyllostica paulowniae is particularly common. The fungus leaves yellow-grey spots on the upper surface of the leaves. It is not necessary for the hobby gardener to interveneFungal infestation leaves no serious signs of damage. Infested leaves should be removed and disposed of with household waste. The fungus can continue to multiply unhindered on the compost.
Snails are also more common on the blue bell tree. The scars on the leaves are clearly visible. Snail infestation does not pose any immediate danger to the crop either. It is sufficient to collect the snails from the leaves and put them back on the ground in a suitable place.
My Kaiserbaum doesn't bloom
Unfortunately, this can happen in our latitudes, especially where there is a harsher climate. As already mentioned, the bluebell tree creates its flowers in autumn. Severe frosts can cause the flowers to freeze and they will not flower the following year.
Wintering the Bluebell Tree
Only mature trees are classified as frost hardy. This means temperatures down to -15 degrees are tolerated. Young plants do not tolerate frost. It is therefore necessary to spend the winter indoors.
Tip: So that the trees do not have to be planted out before the onset of winter, it makes sense to keep the blue bell tree in a bucket for the first two years.
The hibernation should be bright and frost-free. The thermometer should not fall below five degrees. If no more late frosts are to be expected, the plant can go back outside.
Heavy frosts can endanger flowering. Individual shoots can be wrapped with garden fleece as a protective measure. In areas with a harsher climate, a layer of mulch will protect mature cedar trees from frost damage.
Is the bluebell tree poisonous?
The leaves of the emperor tree are edible. They are reminiscent of spinach and are used as food in Asia. The fruits of the blue bell tree, on the other hand, are slightly poisonous. However, the danger that someone will eat them voluntarily is exceptionally low because they are inedible.