Independent comparisons. We may earn from shop links. More info

Bonsai compost or akadama

Updated: October 2026

A club page says leave multipurpose compost out of the pot, and an amazon.co.uk title says the bag suits every bonsai. Bonsai compost or akadama is that choice, with bark, grit and sand sitting between them. Akadama with pumice and lava is a granular mix. Fine multipurpose on its own stays out of the bonsai pot. None of the listings on the [bonsai compost comparison](/hub/fertiliser-soil-and-bark-mulch/bonsai-compost) names those granules. The Products Compared editorial team used club and RHS pages and the titles, updated 19 October 2026. A qualifying purchase can earn a commission at no extra cost to you.

A club page says leave multipurpose compost out of the pot, and an amazon.co.uk title says the bag suits every bonsai. Bonsai compost or akadama is that choice, with bark, grit and sand sitting between them.

Our top picks

Miracle-Gro Miracle-Gro cactus, succulent and bonsai compost 6 litres

Best overall

Miracle-Gro Miracle-Gro cactus, succulent and bonsai compost 6 litres
7.8/10about £9.79
View offer
UK GROW UK GROW Bonsai Focus 5 litre bucket

Rank 2

UK GROW UK GROW Bonsai Focus 5 litre bucket
8.6/10about £10.99
View offer
UK GROW UK GROW bonsai potting mix 30 litres

Preis-Tipp

UK GROW UK GROW bonsai potting mix 30 litres
6.6/10about £18.99
View offer
On this page
  1. 1.Three different things sold as bonsai soil
  2. 2.What clubs put in the pot
  3. 3.The RHS route if you mix at home
  4. 4.When compost, when akadama

Three different things sold as bonsai soil

Multipurpose compost is a fine mix for beds and general pots. BBC Gardeners' World says it can stay too wet in a bonsai pot and can lead to root rot. This Amazon set is the middle product. Focus titles name composted bark, grit and fine sand. Invigortex and the plain UK GROW bags do not name the particles. None of them is akadama. Akadama is baked clay, usually mixed with pumice and lava. British Bonsai says not to use it alone in the UK because freeze-thaw breaks it down. That is a seller's warning, not a lab test. How to read the bags is on the bonsai compost buying guide.

What clubs put in the pot

Club ratios are starting points. Bonsai Empire describes about 50 per cent akadama, 25 per cent pumice and 25 per cent lava for deciduous trees, and about a third of each for conifers. Cheshire Bonsai Society uses 2:1:1 akadama, lava and pumice for older maples and 1:1:1 for conifers. The scoops differ. They agree a pine should not sit in mostly fine compost.
Miracle-Gro Miracle-Gro cactus, succulent and bonsai compost 6 litres

Testsieger

Miracle-Gro Miracle-Gro cactus, succulent and bonsai compost 6 litres
7.8/10about £9.79
View offer

The RHS route if you mix at home

The RHS home mix is two parts peat-free potting compost, two parts sharp sand or lime-free alpine grit, and one part peat-free John Innes No. 3. Lime-haters should use ericaceous compost instead. That is compost and grit, not akadama, and it works for a first pot only if you add the grit.

When compost, when akadama

A bark, grit and sand bag is enough for a first repot of a small garden-centre tree, if the title names those materials and you water by feel. The 5 litre Focus bucket at £10.99 is the closable tub with the largest Focus review file. It is a poor match for a pine you will keep for years. Choose akadama, pumice and lava for a tree you mean to keep. Use more akadama for maples, and a drier mix for pines. Indoor tropicals can hold a little more moisture. Those bags are on indoor bonsai compost. The repot sequence is on how to repot a bonsai.

Common questions

Is akadama a compost?
Akadama is a hard clay granule, usually mixed with pumice and lava. It is not garden compost and not the bark, grit and sand tubs in this Amazon set. It holds some water in the gaps and does not feed the tree, so you still use a light fertiliser. Used on its own in a British winter it can break down.
Can I use multipurpose compost for bonsai?
Fine multipurpose compost on its own stays too wet in a shallow bonsai pot. BBC Gardeners' World links that wetness, with overwatering, to root rot. The RHS home recipe uses peat-free potting compost only as one part, with as much sharp sand or lime-free grit, plus a smaller share of peat-free John Innes No. 3. If you will not add the grit, leave the multipurpose bag for the beds and the seed trays.
What mix do UK clubs describe for maples and for pines?
Cheshire Bonsai Society describes 2:1:1 akadama, lava and pumice for older maples and 1:1:1 for conifers. Bonsai Empire is close: about half akadama for deciduous trees, and about a third each for conifers, with more grit in a wetter climate. Miyagi Bonsai uses a similar deciduous split and says pines should avoid a mix with much compost. These are starting points, not the only correct scoop, and they are not what these Amazon bags contain.
What if I will not buy imported clay?
Use a bark, grit and sand compost whose title names those materials, or mix the RHS recipe from peat-free compost, sharp sand or lime-free alpine grit, and peat-free John Innes No. 3. That is a fair first repot for a small garden-centre tree if you water by feel. It will not copy the granule size of akadama. For an azalea, switch the compost part to ericaceous. Lime-containing John Innes is the wrong base.
Does akadama feed the tree?
No. The granules are inorganic, and Cheshire Bonsai Society says you have to feed. A compost bag is not automatically a feed either. The RHS still expects a low-dose balanced liquid fertiliser in the growing season after any slow-release from repotting is spent. Read the bottle for the rate. The Amazon bullets in this set do not give you that rate.
Why not use akadama on its own in Britain?
British Bonsai warns that freeze-thaw breaks akadama down, so they would not use it neat in the UK. Bonsai4me says akadama alone can collapse within one or two years, and that pines should not be potted in it alone. Blend it with pumice and lava, and keep some old soil on a pine when you repot. A hard winter in an exposed garden can turn a pot of pure akadama into a denser mass that stops draining.
Is a bark, grit and sand bucket the same thing as akadama?
No. A Focus-style bucket is composted bark with grit and fine sand. Akadama is fired clay with pumice and lava, and none of these listings names it. The bucket fits a first small tree when the title names drainage materials. The granular mix is the club choice for a tree you will keep, plus fertiliser, because the granules do not feed.

Related pages

Bonsai compost

Best bonsai compost for the job in front of you

Bonsai compost buying guide: five pre-buy checks

How to repot a bonsai into fresh open compost

Indoor bonsai compost on a British windowsill

Sources

Public UK sources from the research digest, used for this page in October 2026. Prices, stars and review counts are the figures stored from the eleven amazon.co.uk listings in this set. A drainage line, an all-types line and a peat-free line are listing claims. This is not a laboratory test. Selling peat compost was not shown to be an England-wide offence on 19 October 2026.

  1. RHS, bonsai advice (retrieved October 2026)
  2. RHS, peat-free exhibitor tips (retrieved October 2026)
  3. RHS, retail peat-free from January 2026 (retrieved October 2026)
  4. GOV.UK, Defra peat sales announcement, 27 August 2022 (retrieved October 2026)
  5. UK Parliament deposited paper DEP2026-0072, 29 January 2026 (retrieved October 2026)
  6. Bonsai4me, an introduction to bonsai soils (retrieved October 2026)
  7. Cheshire Bonsai Society, Japanese maples as bonsai (retrieved October 2026)
  8. BBC Gardeners’ World, indoor bonsai tree care (retrieved October 2026)