When and how do you repot bonsai? In the video, Melissa shows how to proceed correctly when repotting the mini tree and what you have to consider when choosing the pot and the substrate.
Video instructions for transplanting bonsai [music: www.bensound.com]
Bonsais regularly move to new pots or trays when their roots can no longer find a morsel of fresh substrate. When repotting bonsai, however, there are a few important things to consider that are crucial for a he althy bonsai. We explain when you should repot the bonsai, whether to cut its roots and which soil is best suited for bonsai.
When should you repot your bonsai?
Bonsai are best repotted in spring. You can tell from the "top growth" of the roots that it is time to provide your bonsai with new soil and possibly a larger pot. You can check this very easily: Take the bonsai together with the root ball out of the bowl and check whether the roots have reached the edge of the container. They then begin to grow in circles along it.
Young and fast-growing trees are repotted annually on average, while older specimens only need to be repotted every three to five years.
Even if the bonsai -Soil is no longer loose, mold or algae are forming and the bonsai leaves hanging despite watering, it is important to repot quickly. In this case, the substrate is too old and sagging, and the bonsai's roots are threatened by a lack of oxygen and rotting agents.
By the way: Even brand new bonsais usually have to be repotted. Because for the long dry spells during transport and storage before sale, the trees are potted in a "travel substrate" that stores water better. However, this substrate is completely unsuitable for permanent culture and should be replaced as soon as possible with a high-quality bonsai soil - for example Floragard bonsai soil. An exception are very high-quality bonsai from specialized bonsai nurseries - they are usually delivered in suitable soil.

Repotting bonsai: instructions on how to proceed
Repotting bonsai is not difficult. In addition to a few materials and tools, a suitable bonsai soil is essential. We have put together detailed instructions for bonsai repotting at the end of this article.
You need this
To repot your bonsai properly, you need:
- A larger bonsai pot if the bonsai is still to grow. If the bonsai should keep its current size, the old pot can be reused and the roots cut.
- Small netting or wire mesh.
- Clay pebbles.
- Pruning shears.
- If the bonsai is held in the pot with wire: side cutters.
- A pricking stick or a long wooden stick.
- A watering can.
- A small shovel.
- A suitable bonsai soil.

The right soil for repotting bonsai
Since the bonsai is only allowed a tiny volume to spread its roots, this small space must be filled with good quality and suitable soil. A very important quality criterion for bonsai soils is high structural stability. This is important because structurally stable materials do not decompose as quickly and therefore do not collapse as easily, but remain airy for a long time. Often, but not always, structural stability is achieved through a high proportion of mineral components.
However, each species of tree prefers a different substrate. Therefore, it is best to create the ideal mix for each bonsai using a good quality bonsai soil as the basic substance. The Floragard bonsai soil, for example, satisfies the high demands of bonsai and thus provides a good basis for the individual soil mix of your bonsai. Gravel, perlite, clay minerals, expanded clay and sand can then be mixed into the bonsai soil, for example. You can find out which mixture is the right one for your own bonsai in our article on the most popular bonsai species.
The bonsai is repotted in these 6 steps:
- Detach the bonsai from its old pot. If the root ball is fixed with wire, it is first clipped and bent open with the side cutter. Sometimes it helps to run a knife along the edge of the shell to loosen the root ball.
- If the surface of the bonsai is intentionally planted with moss,this can be carefully lifted off and put aside.
- Use a pricking stick to remove excess soil from the root ball as much as possible. But be careful not to damage the roots.
- Prepare the bonsai pot: Secure the trellis with wire over the holes in the bottom of the pot. Then the bottom of the pot is covered with expanded clay and a layer of the right bonsai soil.
- Now insert the bonsai and fill the rest of the pot with substrate. Make sure that the tree does not sit too deep in the substrate: the entire stem should be exposed.
- Finally, the little tree is watered, the moss put back on and also moistened.
Tip: If necessary, you can also make the design cut when repotting the bonsai. A root cut is also a good idea for fast-growing trees that need to be tamed. Here, only the outer root tips are shortened with a sharp knife or pruning shears. You can find out more about design and root pruning in our special article on the topic "Pruning bonsai".

Care for bonsai after repotting
Even after repotting, you can water and fertilize the bonsai as usual. Since the repotting takes place in spring, the bonsai - if it is summer green - will soon sprout afterwards. Is your bonsai not sprouting or are all the leaves falling off? We have compiled possible reasons why your bonsai is losing leaves.
Many thanks to Floragard for the support!