Help, my bonsai is dying
It is impressive how often this sentence is uttered on Bonsai Fora. Many stores offer small bonsai for a few dollars. With a few short instructions (This indoor bonsai needs a bright spot out of direct sunlight. Put the tree in a bowl of water once a week to fully water the plant) people get home. And after a few days the first leaves get brown and start to fall of. Enjoyment makes way for utter disapointment. So, what has gone wrong and how can you turn a dying bonsai into a thriving green ball?
The main thing is to figure out what is happening to your tree that makes it drop the leaves. Although several species of trees are sold as mallsai (e.g., ficus, sageretia theezans, chinese elm), often similar problems occur:
- Leaves turn crisp, either green or with brown edges
- Leaves drop in quick succession
Most of these problems can be traced back to trouble in keeping the water provision to the leaves up to par. This may mean that the dry room air may crisp the leaves, the roots of the plants are too wet or the roots of the plants are too wet. How to try and salvage the damage.
First of all, realize that pretty much all plant species prefer the outdoors over de indoors. Some will do well indoors, or have to spend time indoors when the climate outside is unsuitable. Some species however, will never survive indoors. To this belong all the temperature tree species (Junipers, Chamaecyparis, Apples, Beech, Maples). When you try to grow these indoors, especially in winter, you run the risk of a dying tree very quickly. No matter what you were told in the shop: Junipers, Pines, Picea etc should be kept outside. Always. Unless you bought the plant in winter, place the tree outside, sheltered from rain. In winter, find an unheeted room, and keep it there. (In another article I will explain why you should never place a bonsai outside in the middle of winter, if purchased from a neated greenhouse).
Sageretia, Ulmus and ficus may be kept in the living room for winter but ideally they are moved outside for summer). Make sure they are in a bright spot, but ideally not above a radiator. If the only space you have is over a radiator, place a tray with water under the plant (Note: The pot shoudl not be standing in the water!). This should help to raise humity levels somewhat.
Secondly, check the soil of the bonsai. If it is covered with glued-on stones, you can probably throw your plant away. These rocks are glued on for transport from China to wherever you bought the plant. The stones prevent proper watering, and the roots have become either too dry or too wet, in both cases resulting in dead roots. A plant with dead roots is a dead plant, unless you are very skilled in horticulture (In which case you most likely would not be reading this thread). Remove the stones and check the roots.
Thirdly Check the roots of the bonsai. Gently pull the plant from the container. It may be that the plant is secured in the pot with a wire. At the underside of the pot, clip the wire to release the plant from the pot. Check whether the roots are healthy -white tipped, brownish etc rather than a pure black and/or slimy-. If they are, then consider a repot in a pot one size larger, and treat normally. Just do not add any fetilizer to the water until strong growth is obtained.
Of course, you could have just have the bad luck that your plant suffers one of many possible insect infestations. But that is for another post!