Tree or shrubtree ornamentalSome care needed

Japanese maple

Acer palmatum

Grown for leaf shape and autumn colour rather than flowers, slow enough to suit a courtyard and one of the few good trees for a large pot. Its two enemies are both about air rather than soil: cold spring wind scorches the young leaves, and hot afternoon sun crisps the finely cut forms.

Position: Dappled shade or Partial shade
Water: moderate demand
Drainage: Moisture-retentive, Free-draining
Grows to: 200–600 cm × 200–500 cm
Hardiness: H6
Difficulty: Some care needed

Described view

A Japanese maple leaf with crisp brown margins from wind scorch beside a healthy leaf from a sheltered plant

August

Nothing to do

No sowing, planting, harvesting or pruning window falls in August.

Japanese maple’s year

Resolved for United Kingdom (general). Every window is stored against a climate event rather than a date, so a late frost pocket runs later than the band shows. What else August calls for.

Activity	J	F	M	A	M	J	J	A	S	O	N	D
Plant			March.	April.						October.	November.
Prune	January.										November.	December.

Timing that travels

The band above resolves this plant's windows into months for one region. These are the windows themselves, stored against a climate event rather than a date — which is the form that survives being carried to a colder garden, a frost pocket, or next year.

Conditions it needs

Light: Dappled shade, Partial shade
Frost: Hardy
Hardiness rating: H6 (RHS)
Grows best at: 8–24 °C
Soil: Loam, Peat-free compost
Soil pH: 5–6.8
Drainage: Moisture-retentive, Free-draining
Water needs: moderate
Drought: poor tolerance
Waterlogging: poor tolerance
Heat: poor tolerance
Wind and exposure: poor tolerance

Where these figures come from

LightSourced guidancemoderate confidence

Royal Horticultural Society: Japanese maple — position

Checked 2026-08-13

FrostSourced guidancehigh confidence

Royal Horticultural Society: Japanese maple — hardiness

Checked 2026-08-13

Hardiness ratingSourced guidancemoderate confidence

Royal Horticultural Society: RHS hardiness ratings

Checked 2026-08-13

Grows best atSourced guidancemoderate confidence

Royal Horticultural Society: Japanese maple — temperature

Checked 2026-08-13

SoilSourced guidancemoderate confidence

Royal Horticultural Society: Japanese maple — soil

Checked 2026-08-13

Soil pHSourced guidancemoderate confidence

Plant Finder — Missouri Botanical Garden: Acer palmatum — culture

Checked 2026-08-13

DrainageSourced guidancemoderate confidence

Royal Horticultural Society: Japanese maple — soil

Checked 2026-08-13

Water needsHorticultural consensusmoderate confidence

No external citation — see the evidence type above.

Checked 2026-08-13

DroughtHorticultural consensusmoderate confidence

No external citation — see the evidence type above.

Checked 2026-08-13

WaterloggingHorticultural consensusmoderate confidence

No external citation — see the evidence type above.

Checked 2026-08-13

HeatHorticultural consensusmoderate confidence

No external citation — see the evidence type above.

Checked 2026-08-13

Wind and exposureHorticultural consensusmoderate confidence

Cold drying wind browns the leaf margins within days.

No external citation — see the evidence type above.

Checked 2026-08-13

On your soil

Computed by comparing this plant's recorded requirements against each soil's recorded characteristics. A recorded horticultural fact overrides the comparison where GrowingHQ holds one.

Soil	Verdict	Why
Heavy clay	Works, with one condition	Japanese maple will crop on heavy clay, but one thing has to be dealt with first. It needs ground that drains, and this soil holds water. A plant that stays in the ground through winter with its roots in cold, saturated soil rots — which is what kills most of what fails on heavy ground, rather than the cold.Improve the drainage before planting — a raised bed, or bulky organic matter worked in over several seasons. Do not add sand to clay in small quantities; it makes the problem worse.
Sandy	Works, with one condition	Japanese maple will crop on sandy, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Chalky and alkaline	Struggles here	Japanese maple struggles on chalky and alkaline: The soil is substantially too alkaline for it: it wants pH 5 to 6.8, and this soil sits around 7.8 to 8.5. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering. A container or a raised bed of imported soil sidesteps the problem entirely.
Loam	Prefers this soil	Loam suits Japanese maple as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. The soil holds moisture, which saves a great deal of watering.
Silty	Grows well here	Japanese maple grows perfectly well on silty without special measures, though it is not the soil it would choose.
Peaty and acid	Works, with one condition	Japanese maple will crop on peaty and acid, but one thing has to be dealt with first. It needs ground that drains, and this soil holds water. A plant that stays in the ground through winter with its roots in cold, saturated soil rots — which is what kills most of what fails on heavy ground, rather than the cold.Improve the drainage before planting — a raised bed, or bulky organic matter worked in over several seasons. Do not add sand to clay in small quantities; it makes the problem worse.
Shallow over rock	Works, with one condition	Japanese maple will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Made ground and urban soil	Works, with one condition	Japanese maple will crop on made ground and urban soil, but one thing has to be dealt with first. It needs ground that drains, and this soil holds water. A plant that stays in the ground through winter with its roots in cold, saturated soil rots — which is what kills most of what fails on heavy ground, rather than the cold.Improve the drainage before planting — a raised bed, or bulky organic matter worked in over several seasons. Do not add sand to clay in small quantities; it makes the problem worse.

Not sure which you have? Four hand tests will settle it.

Space and spacing

Mature height: 200–600 cm
Mature spread: 200–500 cm
Rooting depth: 60 cm
Spacing: 250–400 cm apart

Where these figures come from

Mature heightHorticultural consensusmoderate confidence: No external citation — see the evidence type above.
Checked 2026-08-13
Mature spreadHorticultural consensusmoderate confidence: No external citation — see the evidence type above.
Checked 2026-08-13
Rooting depthHorticultural consensusmoderate confidence: No external citation — see the evidence type above.
Checked 2026-08-13
SpacingSourced guidancemoderate confidence: Royal Horticultural Society: Japanese maple — spacing
Checked 2026-08-13

Measured centre to centre. Plants set closer than this compete for light and water long before they look crowded, and the crowding cannot be undone once they are in.

Habit and ultimate size

What the plant becomes, rather than what it is when you buy it. The gap between the two is where most planting mistakes live.

Foliage: Deciduous
In a container: Good in a container long-term

Where these figures come from

FoliageSourced guidancehigh confidence: Royal Horticultural Society: Acer palmatum — foliage
Checked 2026-08-13
In a containerHorticultural consensusmoderate confidence: No external citation — see the evidence type above.
Checked 2026-08-13

Growth rate: Slow — under about 30 cm a year
Ultimate height: 200–600 cm
Ultimate spread: 200–500 cm
Time to reach it: 20–40 yearsSourced guidance

Where these figures come from

Growth rateSourced guidancemoderate confidence: Royal Horticultural Society: Acer palmatum — growth rate
Checked 2026-08-13
Ultimate heightSourced guidancemoderate confidence: Royal Horticultural Society: Acer palmatum — ultimate height
Checked 2026-08-13
Ultimate spreadSourced guidancemoderate confidence: Royal Horticultural Society: Acer palmatum — ultimate spread
Checked 2026-08-13
Time to reach itSourced guidancelow confidence: Royal Horticultural Society: Acer palmatum — time to ultimate size
Checked 2026-08-13

Cutting it back. Thin to reveal the layered branch structure rather than shortening branches, and only in late autumn or early winter — acer bleeds from spring cuts. One of the few trees genuinely good in a large pot for decades.

source

Horticultural consensusmoderate confidence

No external citation — see the evidence type above.

Checked 2026-08-13

Where and how you can grow it

Each way of growing is assessed separately, and “not assessed” is a real answer rather than a gap we have filled in with a guess.

Method	Suitability	What it needs
Open ground	Well suited source Sourced guidancemoderate confidence Royal Horticultural Society: Growing method suitability Checked 2026-08-13
Traditional dug bed	Workable source Sourced guidancemoderate confidence Royal Horticultural Society: Growing method suitability Checked 2026-08-13
Container	Workable source Sourced guidancemoderate confidence Royal Horticultural Society: Growing method suitability Checked 2026-08-13
Raised bed	Marginal source Sourced guidancemoderate confidence Royal Horticultural Society: Growing method suitability Checked 2026-08-13	A raised bed rarely holds enough soil volume for a tree beyond its first few years.

Growing it

PlantingGive it shelter from wind above everything else. Dappled shade with protection from cold easterlies and from hot afternoon sun is the position; the finely dissected forms are the most sensitive, and an exposed one browns at the leaf edges by June every year regardless of watering.
PruningPrune in late autumn or early winter and keep it minimal. Acer bleeds heavily from late-winter and spring cuts, and the naturally layered branch structure is the reason to grow one — thinning to reveal it is worthwhile, shortening branches is not.

Where this guidance comes from

PlantingSourced guidancehigh confidence: Royal Horticultural Society: Acer palmatum — position
Checked 2026-08-13
PruningSourced guidancehigh confidence: Royal Horticultural Society: Acer — pruning
Checked 2026-08-13

The bud you cut to becomes the new shoot, and it grows in the direction it points — which is why an outward-facing bud opens the plant up and an inward-facing one crosses the middle.

Sources for this page

GrowingHQ editorial synthesis · Plant Finder · Royal Horticultural Society

Each figure on this page carries its own citation, under the “where these figures come from” note in its section. Record last reviewed 2026-08-14.

If something is wrong with it

Crisp brown edges around the leaf margin — 2 causes GrowingHQ holds for japanese maple

Something else? Work through it with the diagnostic tool.