A comprehensive guide when to repot and which soil mix you should use for the most popular conifers
Pinus thunbergii
Black pine
When to repot:
Start of March to middle of April, until the candles start to grow.
Soil mix:
Akadama: 5 Kiryu: 2 Mountain sand / Grit: 3
Points of caution:
Once a tree reaches a state of completion, reduce the amount of grit and increase the Akadama. Fertilise one month after repotting.
Pinus densiflora
Red pine
When to repot:
Start of March to middle of April, until the candles start to grow.
Soil mix:
Akadama: 6 Fuji: 3 River sand: 1
Points of caution:
The soil must be better aerated than with black pine..
Pinus parviflora
White pine
When to repot:
Start of March to middle of April, until the candles start to grow.
Soil mix:
Akadama: 7 Kiryu: 2 Grit: 1
Points of caution:
For younger trees, you can use more grit. It is important to have good aeration in the soil, so good drainage is essential.
Juniperus chinensis
Juniper
When to repot:
From the start of March, but it is better once it has warmed up a little in May.
Soil mix:
Akadama: 7 Kiryu: 1 River sand: 2
Points of caution:
It can withstand a hard root pruning, so aim to hold back strong roots in favour of fine.
Juniperus rigida
Needle juniper
When to repot:
Middle of April to the end of May.
Soil mix:
Akadama: 5 Kiryu: 1 River sand: 4
Points of caution:
They love water so increasing Akadama is a good idea.
Picea glehnii
Ezo spruce
When to repot:
Start of March to middle of April, until the candles start to grow
Soil mix:
Akadama: 8 Kiryu: 2
Points of caution:
Use a fine particle soil mix.
Taxus cuspidata
Japanese yew
When to repot:
Start of February to the end of March. Before the shoots open
Soil mix:
Akadama: 6 Kiryu: 4
Points of caution:
Once a tree has reached a finished state, the soil mix should be water retentive and also well aerated.
Cedrus
Cedar
When to repot:
End of March to the end of June
Soil mix:
Akadama: 6 Kiryu: 1 River sand: 3
Points of caution:
They like water and so you can increase the amount of Akadama if necessary.
Chamaecyparis
Hinoki cypress
When to repot:
End of March to end of April
Soil mix:
Akadama: 6 River sand: 3 Kiryu: 1
Points of caution:
They like a lot of food and water so take care the roots do not become compacted. Mist the foliage after repotting.
Tsuga canadensis
Hemlock
When to repot:
End of February to start of March
Soil mix:
Akadama: 8 Kiryu: 2
Points of caution:
The roots will become very soft once the temperature warms up and they tear apart. Do it earlier rather than later.
