Repotting your bonsai

The repotting is an important and delicate step in the growing of bonsai. This step not only allows renewing the substrate as it has a tendency to become impoverished and subside over time, but also to stimulate the roots which renew a part of their root-hairs.

Repotting your bonsai

At which frequency must I repot my Bonsai?
Generally every two years for a young specimen and every three to five years for an older one. The repotting offers a real rejuvenating's therapy to the bonsai but must only be done on a vigorous specimen. If your bonsai is not healthy, another option consists of planting it in the ground, for a few months or an entire year, in your vegetable plot for example. It will then regain vigour and will be in a great shape for its repotting!

Which substrate must I use?
The substrate must have two main qualities: retain water and be well-drained. The ‘Akamada' (red ball earth) has these two properties but it is also often difficult to get hold of. You can mix, in equal parts, clay, sand and potting compost or mix horticultural compost with zeolite. Of course, you must adjust the mix according to the area you live in: you will have to choose a highly draining substrate in wet areas and, on the contrary, chose a water-retaining substrate in hot and dry areas. You also need to adapt the substrate to the specific requirements of the plant. For species such as beech tree, pine tree or Juniper tree, mix a little bit of the old substrate with the new one as it contains essential mycorrhizas which are vital for good roots development.

Which container must I choose?
There is a multitude of pots designed to grow bonsais in, plain or ornate, round, rectangular, of different depths and different colours. It is not easy to get your bearings especially as prices can quickly increase.
A basic principle consists in respecting a balance between the general shape of your bonsai and the pot: you have to choose a pot which will slightly wider or higher than the bigger dimension of your bonsai, by 2/3. For example, for a bonsai wider than it is high, the pot will be slightly bigger than two thirds of the bonsai width.
You must keep in mind that the container must enhance the tree and that it must be chosen according to your climate : it is difficult for example to grow a bonsai in a fairly flat pot under a hot and dry climate as the evaporation is likely to be too rapid.

A few tips: Only repot your bonsai if it is vigorous and healthy, use a highly draining substrate which also offers good water-retention, adapt it to your climate, and finally ensure a good homogeneity to your substrate.

 
Pépinières PLANFOR
1950 Route de Cère
40090 UCHACQ - FRANCE
Tel : (020).7660.0178
Fax : 0033 558 064 854