Fertilising guide
How to fertilise Japanese Larch (Larix kaempferi)— schedule & NPK
Also called Japanese Larch.
More about japanese larch
About Japanese Larch
Larix kaempferi · also called Japanese Larch · flowering
Japanese larch (Larix kaempferi) is a deciduous conifer popular as bonsai for its soft blue-green needle tufts, reddish winter twigs and brilliant gold autumn colour before needle drop. It bears small cones and is wind-pollinated. Fast and vigorous, it loves full sun, generous water and a proper cold winter.
Growth habit: Deciduous conifer with strong apical growth, horizontal-to-drooping branches and reddish young shoots; needles emerge in soft rosettes on short spurs. Vigorous and back-buds readily, making it forgiving for bonsai training.
Watch for — Weak growth in shade: Insufficient light causes sparse, elongated, pale needles; site in full sun for compact, vivid foliage.
What fertiliser japanese larch actually wants — and why
Japanese Larch is an easy, light foliage feeder — a half-strength balanced liquid feed through the growing months keeps it green without forcing weak, sappy growth.
A balanced general houseplant feed (roughly even N-P-K) is exactly right — it is grown for foliage, so steady, moderate nitrogen for healthy leaves is the goal, not a bloom or root formula.
For the language behind the three numbers on the bottle — what nitrogen, phosphorus and potassium each do — see the NPK ratio explained entry. The short version for japanese larch: match the feed to the job the plant is doing right now, not to a generic “plant food” on the shelf.
How often to feed japanese larch, and which months
Feeding only earns its keep while the plant is in active growth and can use the nutrients — pour feed into a dormant or low-light plant and it simply builds up as root-burning salt. For japanese larch:
Feed generously with balanced organic fertiliser from bud break through summer to fuel its vigour, tapering off in early autumn. Larch responds well to feeding but withhold during the late-summer needle-hardening period to keep growth compact. Treat that as sparingly through the growing season between spring through early autumn (roughly March to September); ease off in autumn and stop entirely in the low light of winter.
The dormant-season rule matters more than the exact interval: skip feeding entirely when japanese larch is resting. For the wider context on indoor feeding rhythms across the seasons, the houseplant fertiliser schedule walks through the year month by month.
What strength to mix for japanese larch
Half strength is the safe default for japanese larch — houseplant feeds are formulated strong, and the diluted dose is gentler on the roots while still ample for foliage.
Feeding always goes onto already-damp soil, never dry roots — water japanese larch first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the japanese larch watering schedule.
Signs you are over-feeding japanese larch
Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for japanese larch:
- Brown, crispy leaf tips and edges with no sign of underwatering.
- A white, crusty salt deposit on the soil surface or pot rim.
- Weak, pale, stretched new growth that flops.
- Lower leaves yellow and drop while the soil is correctly watered.
Signs you are under-feeding japanese larch
- Uniformly pale or yellow-green leaves, oldest first.
- Noticeably small new leaves and stalled growth in good light and season.
- A generally tired, lacklustre look despite correct watering and light.
If the symptoms point at watering, light or roots rather than nutrition, the full japanese larch care brief covers soil, humidity and the common problems for this species.
Flushing and leaching the salts
Flush the pot of japanese larch with plain water until it runs freely from the base every couple of months in the feeding season — it washes out the fertiliser salts that cause brown tips.
Organic vs synthetic feeds for japanese larch
Organic options
A diluted seaweed or worm-casting feed, or fish emulsion if you can tolerate the smell indoors. UK: Westland or Baby Bio Organic, dilute seaweed; US: Espoma Indoor! or Neptune's Harvest fish & seaweed. Slow, gentle and hard to overdo.
Synthetic / liquid feeds
A general-purpose houseplant liquid at half strength — UK: Baby Bio, Westland Houseplant Feed or Phostrogen; US: Miracle-Gro Indoor Plant Food or Schultz. Convenient and fast-acting; the only risk is overdoing it.
Brand names are examples, not endorsements, and UK and US ranges differ — check the label’s own NPK and dilution rate, since formulations change.
Fertilising japanese larch — frequently asked questions
What fertiliser does japanese larch need?
A balanced general houseplant feed (roughly even N-P-K) is exactly right — it is grown for foliage, so steady, moderate nitrogen for healthy leaves is the goal, not a bloom or root formula. Japanese Larch is an easy, light foliage feeder — a half-strength balanced liquid feed through the growing months keeps it green without forcing weak, sappy growth.
How often should I feed japanese larch?
Feed generously with balanced organic fertiliser from bud break through summer to fuel its vigour, tapering off in early autumn. Larch responds well to feeding but withhold during the late-summer needle-hardening period to keep growth compact. Feed generously with balanced organic fertiliser from bud break through summer to fuel its vigour, tapering off in early autumn. Larch responds well to feeding but withhold during the late-summer needle-hardening period to keep growth compact. Treat that as sparingly through the growing season between spring through early autumn (roughly March to September); ease off in autumn and stop entirely in the low light of winter.
What strength of feed for japanese larch?
Half strength is the safe default for japanese larch — houseplant feeds are formulated strong, and the diluted dose is gentler on the roots while still ample for foliage.
What does over-feeding japanese larch look like?
Brown, crispy leaf tips and edges with no sign of underwatering. A white, crusty salt deposit on the soil surface or pot rim. Weak, pale, stretched new growth that flops. Lower leaves yellow and drop while the soil is correctly watered. Feeding japanese larch year-round on a fixed schedule, including dark winter months, is the most common mistake — it cannot use the nutrients in low light and the surplus simply burns the roots and crusts the soil.
Should I flush the soil of japanese larch?
Flush the pot of japanese larch with plain water until it runs freely from the base every couple of months in the feeding season — it washes out the fertiliser salts that cause brown tips.
Keep reading
- Japanese Larch care — the full brief (light, soil, humidity, problems, pet safety)
- How often to water japanese larch — the watering schedule
- The houseplant fertiliser schedule — feeding through the year
- NPK ratio explained — what the three numbers on the bottle mean
- How to fertilise peace lily
- How to fertilise bird of paradise
- How to fertilise hoya
- All 5561 fertilising guides in the Growli library