Bonsai is generally considered to be a difficult roommate. Caring for them requires precise knowledge and if handled incorrectly, the miniature trees quickly shed their leaves and perish. Read here what this could be.
Anyone who has little experience with caring for a bonsai tree can quickly become confused when the plant shows signs of leaf loss. That’s right because a loss of leaves on bonsai is usually a warning signal that something is wrong – and yet no reason to panic! If you inform yourself a little about the correct bonsai care before buying, then you can enjoy the little piece of jewelry a lot later and avoid care mistakes. We have summarized for you what causes the bonsai to suddenly lose its green leaves and what measures you can take if your bonsai leaves fall.
In a nutshell: why do the bonsai lose its leaves?
- Wrong pouring
- Wrong location
- Nutritional deficiency
- Diseases and pests
Are you watering your bonsai properly?
As is so often the case, the fall of leaves in indoor plants can be an indication of incorrect watering. In particular, cheap DIY store bonsais are often found in pots that are too small with a substrate that is too firm and a lack of water drainage, which leads to several watering problems. It is essential to move a new bonsai into a bowl with a drainage hole and a structurally stable, permeable substrate.
When watering your bonsai, pay attention to the following points: Bonsai is in very small bowls. This artificial restriction of the root space ensures, among other things, that the trees remain small. However, this also means that the planter only contains very little water-storing substrate from which the plant can supply itself.
In summer, bonsais also enjoy a shower from above
Depending on the bonsai design, watering from above is often difficult. It is, therefore, better to immerse the planter once a week so that the entire root ball is well moistened. Then let the excess water drain well. Before the next watering, the upper layer of soil should be well dried out. The far bigger problem, however, is too much irrigation water, because if the bonsai is permanently too wet, the roots rot and the tree is lost. A root ball that is too wet is one of the few good reasons for repotting the bonsai quickly in fresh, dry soil. Remove rotten roots and water sparingly soon.
Is your bonsai in the right place?
All bonsais are very hungry for light. Therefore, place the small trees in as bright a place as possible without direct sunlight. Some species can withstand morning and evening sun, but all bonsais – indoor and outdoor – should be protected from the blazing midday sun. If the bonsai suddenly loses its leaves in autumn, the usual location may no longer offer enough light in the worsened light conditions in winter.
The bonsai then reacts by shedding the inner petals, as these consume more energy than they generate through photosynthesis. If this is the case, look for a lighter place with a more favorable angle of incidence for your bonsai in winter. In the case of sensitive or valuable specimens, it is worth using a plant lamp during the dark season.
Do you fertilize your bonsai as needed?
If you fertilize your bonsai with mineral liquid fertilizer or nutrient salts, you should strictly adhere to the manufacturer’s instructions for dosing. It is better to fertilize your bonsai a little less than too much. Because if an excessive amount of nutrient salts accumulate in the substrate, the roots can no longer absorb water and burn under the salt load – the bonsai reacts by shedding its leaves.
To save the tree, you should remove the old substrate, rinse the roots well, and possibly also cut back a little. Then put the bonsai in fresh soil and do without fertilizers for a while. Tip: Organic liquid fertilizer is free from accumulating substances and therefore practically never leads to over-fertilization if handled carefully.
Bonsais radiate harmony and calm
Has there been a change of location?
Who doesn’t know that: No sooner have you carried your new houseplant home from the shop and set it up at the window than it starts to shed its green leaves. This is a natural reaction that is particularly common in bonsai. The leaf loss here is the result of moving from the greenhouse, garden center, or hardware store to the four walls at home. With such a move, the entire living conditions of the bonsai change – light, temperature, humidity, watering frequencies, and much more. Such a change means great stress for the small plant and naturally leads to leaf fall.
Such a stress reaction can also occur in sensitive plants or varieties that tend to fall off (for example the weeping fig) when moving from one room to another or from outside to inside. Don’t make the mistake of moving the tree again, but give it time (plenty of time!) To get used to the new location. Since many bonsais are sensitive to relocation, you should think carefully about the right place for the plant before moving and leave it alone after moving.
Is the bonsai sick or infected by pests?
Of course, as with any houseplant, pests, harmful fungi or plant diseases can also be responsible for the fact that the bonsai loses its leaves. However, this is relatively rare with bonsai. If you suspect your bonsai may be sick, seek help from a professional to accurately identify the disease before treating the plant. Many, especially exotic bonsais, are sensitive to pesticides, which can damage the trees more than they can be cured. Pests should be collected, washed off, or controlled with natural means.
Outdoor bonsai: autumn leaves shed
The Japanese maple (Acer palmatum ‘Deshojo’) loses its leaves in winter
Outdoor bonsai are a specialty of bonsai care. These mostly somewhat larger specimens of weatherproof deciduous and coniferous trees are much more exposed to the change of seasons than indoor bonsai. So it is quite natural for summer green trees to shed their leaves in autumn, just like their big siblings in the garden do. Even conifers like larch (Larix) or primeval sequoia (Metasequoia glyptostroboides) sometimes lose their foliage in autumn and winter. This is a completely natural process and not a maintenance mistake. In the spring these trees sprout reliably again with proper wintering.