How to grow bonsai from seed without rotting the seed
Updated: 21 October 2026
The packet or the Gift Republic kit is already in the house. The leaflet is short, and it is tempting to soak everything tonight. This page is the sowing craft: how to keep the seed from rotting, when to move a seedling, and when to leave it alone. Prices stay on the [bonsai seeds comparison](/hub/seeds-and-plants/bonsai-seeds). Bonsai Empire says there is no special bonsai seed. The same guide suggests a year in the sowing pot before individual pots, and another year before pruning or wiring. No germination rate was measured.
The packet or the Gift Republic kit is already in the house. The leaflet is short, and it is tempting to soak everything tonight.
The packet or the Gift Republic kit is already in the house. The leaflet is short, and it is tempting to soak everything tonight. This page is the sowing craft: how to keep the seed from rotting, when to move a seedling, and when to leave it alone. Prices stay on the bonsai seeds comparison. Bonsai Empire says there is no special bonsai seed. The same guide suggests a year in the sowing pot before individual pots, and another year before pruning or wiring. No germination rate was measured.
Our top picks
| Badge | Product | Species named | Pots included | Listed use | Note | Price | Offer |
|---|---|---|---|---|---|---|---|
| Best overall |  SVI 50 albizia silk tree seeds | Albizia, mimosa silk tree | Not stated | Outdoor | 3.2 | about £5.99 | View offer |
 Gift Republic Gift Republic bonsai seed kit | No. Bullets say mixed bonsai seeds | 5 coconut-husk pots | Indoor | 7.6 | about £12.40 | View offer | |
| Alternative |  SwansGreen 20 purple blue ghost maple seeds | Title says Japanese maple, Acer Palatum | No. One review says there is no pot | Outdoor | 2.2 | about £5.99 | View offer |
On this page
Read the species before you soak
One fridge setting cannot serve a mixed kit. The RHS describes cold, moist stratification below 5°C for about four to 20 weeks, and some species need warmth first. That is a range. A tropical sold as an indoor bonsai may not want the fridge at all. The Gift Republic kit, model GR200006, has four unnamed packets plus five coir pots, five compost discs and five markers. Chilling all four for the same weeks is a guess. Reviews include both sprouts and total failure. Sow a small batch, keep the rest dry and cool, and learn the species from the leaves.
The RHS mentions a nick or a soak for some hard coats. Do not nick every seed. If the packet names Acer palmatum, follow Japanese maple bonsai seeds. Do not paste an eight-week warm spell and an eight-week chill onto pine, elm, or an unnamed disc.
Medium, water, and a cover
Bonsai Empire starts with drainage, then a check that any stratification is done, then a cover and steady moisture. The RHS compost note is peat-free potting compost with sharp sand or lime-free grit, and John Innes No 3 or an ericaceous mix for acid-loving plants. Yorkshire Dales Millennium Trust uses peat-free compost plus grit and says to protect the tray from mice and birds. Some hardy seed needs a second winter.
Coir discs are a fair first medium. Swell one, fill one coconut-husk pot, and sow thinly. Bonsai Southwest's damping-off advice is not to overwater, and to keep air moving. Moist means the surface darkens and does not drip when you tilt the pot. Take a cover off once you see growth. One kit review describes a seedling that died after the fridge. Move from the fridge to a cool room for a few days before a bright windowsill.
Prick out, then wait to train
Prick out when you can see true leaves. Yorkshire Dales Millennium Trust says to hold the leaf, not the stem. Do not bury the stem deeper than it stood. Bonsai Empire's slower version waits about a year before individual pots. Crowded, thin stems should move at true-leaf stage. Three seedlings with room in a coir pot can stay for the first season.
Do not prune or wire in month two. Empire and BBC Gardeners' World put the first real shaping around three years from sowing. A seedling of 8 centimetres is a plant you are keeping alive. Wire on a soft stem scars it. Ask a nursery or a club grower before you wire a trunk you cannot replace. White fuzz means too wet and too still. A stretched seedling wants more light, not more feed.
When the kit still will not name the tree
If you are holding the Gift Republic mix, label each packet, sow a few seeds, and keep the rest. A tropical chilled for months may have been killed. A maple kept at 21°C on a plate may rot. If the title says purple blue ghost and Acer Palatum, read the maple page before the fridge. If you are still deciding whether seed was the right project, that fork is bonsai from seed or a young plant. This page tells you how to keep the seed you have. It does not argue you into a sapling.
Common questions
How do I sow bonsai seeds in the UK?
Confirm the species, complete any chill or warm spell it needs, then sow in a drained, gritty, peat-free mix or a swollen coir disc. Keep the compost moist rather than wet, and give air once a cover has done its job. Protect outdoor trays from mice and birds. A six-week indoor sprout is the BBC line for the indoor sow they describe, not a promise for maple.
Do all tree seeds need the fridge?
No. The RHS range is cold, moist stratification below 5°C for about four to 20 weeks, sometimes after warmth, for dormant species. Tropical seed sold for indoor bonsai often does not need it. An unnamed mix forces a guess. If the packet will not name the plant, do not freeze the whole packet because maple advice was the last thing you read.
What compost should I use if the kit's coir is all I have?
Use the coir disc in the coconut-husk pot for the first sowing. It is in the Gift Republic box for that job. When you prick out, move towards peat-free potting compost with sharp sand or lime-free grit. Acid-loving species want an ericaceous compost or the acid side of John Innes No 3. Coir alone is a start.
How wet is moist?
The compost should feel cool and damp and should not leak when the pot is tipped. A puddle on coir, a closed bag in a warm room, and no airflow are the damping-off conditions Bonsai Southwest warns against. Water, then wait until the surface just starts to lighten. A cover against birds should still let water drain.
When do I move seedlings into their own pots?
Move them when true leaves are easy to hold, and hold the leaf rather than the stem. If the pot is not crowded, Bonsai Empire's slower pace, about a year in the sowing container, avoids disturbing a plant that has only just rooted. Do not pot them deeper than they stood, and do not start pruning because they now have a pot each.
Related pages
Sources
Sources taken from the research digest. Listings were checked in October 2026.
- RHS — Bonsai (retrieved 21.10.2026)
- RHS — Trees and shrubs from seed (retrieved 21.10.2026)
- RHS — Japanese maples growing guide (retrieved 21.10.2026)
- GOV.UK — Bringing plants and wood into Great Britain (retrieved 21.10.2026)
- Plant health information checker (retrieved 21.10.2026)
- The Marketing of Ornamental Plant Propagating Material Regulations 1999 (retrieved 21.10.2026)
- Bonsai Empire — Growing bonsai from seed (retrieved 21.10.2026)
- RP Seeds — Acer palmatum (retrieved 21.10.2026)