Tree · Sapindaceae
Japanese Maple
Acer palmatum
Give it dappled shade, steady moisture, and shelter from wind, and the Japanese maple repays you with color from spring through fall.
Partial shade
Every 3–7 days
USDA 5–8
10–25 ft · 3–7.6 m
Overview
The Japanese maple is a small, slow-growing tree built for the understory, where filtered light and cool roots keep it at its best. It comes in two broad shapes that decide how it looks in a garden. Upright forms grow into rounded little trees, while laceleaf forms mound and weep with leaves cut so fine they look like lace.
Color is the whole point of growing one. The palmate leaves run red, green, bronze, or purple through the season, and in fall they flare into red, yellow, and gold. The April flowers are reddish and easy to miss, so nobody grows this tree for its bloom.
It asks for patience and a sheltered spot. Hot afternoon sun, drying wind, and dry soil all scorch the leaves, so the trick is dappled shade, even moisture, and a thick collar of mulch. Get the site right and it settles in for decades with very little fuss.
Care
The short version: plant it in dappled or afternoon shade out of drying wind, keep the soil evenly moist and well drained, mulch the root zone, and prune only in late fall to winter.
Light
Dappled or afternoon shade suits this tree best, the kind of filtered light it would get under taller trees in the wild. It will take full sun in cooler climates, but in hot, dry, windy spots that sun scorches the leaves. Deep full shade, on the other hand, dulls the color and loosens the form.
Water
Keep the soil consistently moist, and stay on top of it through hot weather, since this tree has little tolerance for drought. A layer of 3 to 4 inches (8 to 10 cm) of mulch under the canopy holds water in and keeps the roots cool. Let the moisture swing in full sun and the leaf edges scorch.
Soil
Plant in moist, rich, well drained loam that runs slightly acidic and holds plenty of organic matter. High-pH ground tends to bring on chlorosis, where the leaves yellow between the veins, so acidic soil keeps the foliage clean and green.
Temperature
The tree is hardy across a wide range, roughly -20°F to 95°F (-29°C to 35°C). Late frost can nip the tender spring growth, which is one more reason to shelter it from the open and the wind.
Humidity
Ordinary outdoor humidity is plenty, so there's no number to chase. Even soil moisture and shelter from wind matter far more than the air, since dry wind is what crisps the leaf edges.
Feeding
Feed once in spring before the leaves break, using a slow-release or balanced fertilizer. Go light: too much feed pushes weak, fast growth and can raise the salt level enough to brown the leaf margins.
Pruning
Keep pruning to a minimum and save it for late fall to mid winter, when the tree is dormant and you're only taking out dead or crossing branches. Cut in spring or summer and it bleeds sap heavily, so timing matters more here than with most trees.
Repotting
For a tree in a pot or trained as bonsai, repot every 2 to 3 years, refreshing the mix and trimming the roots as you go. Watch for roots circling the pot, water running straight through, or foliage that scorches and stalls, all signs it's outgrown its container.
Size & spacing
Left to grow, it reaches 10 to 25 feet (3 to 7.5 m) tall and about as wide, so give it the same kind of room to spread. It grows slowly, which makes it easy to place and forgiving if you misjudge the scale at first.
When to plant
This tree wakes slowly and bleeds sap if you cut it at the wrong time. Plant it in spring or fall while the weather is mild, watch the reddish flowers come and go in April, and save any pruning for the dormant stretch from late fall into winter.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Plant: Spring or fall, in dappled shade sheltered from drying wind and late frost.
- Harvest: Inconspicuous reddish flowers in April; brilliant fall foliage color (red, yellow, bronze, purple).
Hardiness
USDA hardiness zones: 5–8
Temperature: down to -29°C
Troubleshooting
Most Japanese maple trouble shows up in the leaves first, whether from a baking site or a hidden problem in the roots. Read the early signs and you can fix the easy ones before they spread. Match what you see below, then act while it still helps.
Scattered branches wilting and dying back, often on one side
The likely culprit is verticillium wilt, a soilborne fungus that plugs the tree's plumbing and starves whole limbs. You may see dark streaking under the bark, but because it mimics fusarium, the only sure way to know is a lab culture. There's no cure, so prune out the dead wood, keep the tree watered and fed to push new growth, and never replant a susceptible species in that ground.
Fix:
- No cure exists; prune out dead branches and have a certified arborist assess hazardous dieback
- Support the tree with appropriate irrigation and slow-release fertilizer to encourage new growth
- Remove severely affected trees; plant only resistant species in infested soil
Sticky leaves with soft insects on shoots or waxy bumps on bark
Two sap feeders are usually behind this. Aphids cluster on tender new growth, while scale insects fix themselves to bark as hard or waxy bumps, and both leave sticky honeydew that draws sooty mold. Blast aphids off with water or treat them with insecticidal soap, hit scale with dormant oil, and keep an eye out so the next round doesn't get ahead of you.
Fix:
- Hose off aphids with a strong stream of water or treat with insecticidal soap/horticultural oil
- Apply dormant horticultural oil for scale and prune out heavily infested branches
- Conserve natural predators and monitor through the growing season
Brown, crispy leaf edges that curl
This is leaf scorch, and it comes from too much sun, heat, and wind paired with soil that keeps drying out. It shows up first on the most exposed leaves and gets worse in hot, dry spells, while the roots themselves stay healthy. Water deeply and evenly, lay down 3 to 4 inches of mulch, and give the tree afternoon shade or a spot out of the wind.
Fix:
- Water deeply and consistently to keep soil evenly moist
- Apply 3-4 inches of mulch beneath the canopy to cool roots and retain moisture
- Provide afternoon shade or relocate to a site protected from sun and wind
Toxicity
Good news for pet owners: the Japanese maple is not toxic to cats, dogs, horses, or other animals. It carries none of the wilted-leaf danger linked to red maple in horses. A pet that nibbles the leaves might get a mild stomachache from the sheer bulk, so it's still worth steering them away from chewing on it.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats None
Japanese maple isn't toxic to cats, so a curious nibble won't poison one. A cat that eats a lot of any leaf may cough it back up or get a brief stomachache, nothing more.
Dogs None
The tree is safe for dogs, with no toxin in the leaves, bark, or seeds. The only real risk is a big mouthful upsetting the stomach for a day, the same as with most greenery.
Horses None
Horses can graze around this tree without worry. It carries none of the wilted-leaf danger of red maple, which destroys equine red blood cells, so the Japanese maple is a safe substitute near a paddock.
Rabbits Safe
No part of the plant is poisonous to rabbits. As with any new green, introduce it slowly and in small amounts to keep their gut settled.
Livestock Safe
Cattle, goats, and sheep can browse the foliage without harm. Unlike red maple, it poses no risk of the blood damage that worries owners of grazing animals.
Birds Safe
The tree is harmless to birds, which often pick at the winged seeds and shelter in the branches with no trouble.
People Safe
Japanese maple is not poisonous to people. The leaves and sap are sometimes used in cooking and tea, though the tree is grown for looks rather than the table.
Generally non-toxic, but any plant material can cause mild stomach upset if eaten in quantity; discourage pets from chewing foliage.
Varieties
Hundreds of Japanese maple cultivars exist, sorted mainly by leaf shape and growth habit. These are the ones you'll meet most often at the nursery.
Bloodgood
An upright cultivar grown for its deep reddish-purple palmate leaves, which hold their color well into summer when many reds fade.
Crimson Queen
A weeping, mounded laceleaf form whose finely cut red foliage spills over itself like a fountain.
Sango-Kaku (Coral Bark)
An upright tree prized for its soft, glowing yellow fall color, followed once the leaves drop by coral-red young bark that glows brightest in winter.
Seiryu
A rare upright laceleaf that stays green through summer, then turns gold to red in fall, unusual among the weeping threadleaf types.
var. dissectum / subsp. matsumurae
The threadleaf and laceleaf group at large, with deeply and finely cut leaves carried on a low, weeping mound.
How to propagate
Japanese maples are slow and finicky to multiply, and the named cultivars won't come true from seed at all. How you go about it depends on whether you want the exact plant or just the species.
GraftingDemanding
Late winter to early spring (bench grafting onto seedling rootstock). · Several months to a year for the graft union to take and grow on.
Named cultivars won't come true from seed, so grafting is the way the nursery trade reproduces them. The work is bench grafting onto Acer palmatum seedling rootstock in late winter to early spring, and the union then needs several months to a year to knit and grow on. It's demanding, and the recommended route for any cultivar you want to copy exactly.
SeedModerate
Sow stratified seed in fall or early spring. · Seedlings establish over one to several seasons.
Seed works for the straight species, though the seedlings vary and won't match a named parent. Sow stratified seed in fall or early spring and let the young trees establish over one to several seasons. The species self-seeds readily, enough that it's listed as invasive in Virginia and DC, so collect or contain seed where that's a concern.
Stem cuttingsDemanding
Early summer (softwood cuttings). · Weeks to months to root, with low success rates.
Softwood cuttings taken in early summer can root, but they're stubborn and the success rate stays low. Even when they do take, it runs anywhere from weeks to months, which makes this an unreliable choice for most cultivars. Grafting is the steadier bet if you want a faithful copy.
Myths
Japanese maple leaves are dangerously poisonous to dogs and cats.
Acer palmatum isn't on the ASPCA toxic-plant lists, and like the other maples they evaluate, it's treated as non-toxic to cats and dogs. The wilted-leaf danger people have heard about belongs to red maple in horses, not this tree in pets. Japanese maple is safe to plant where pets roam.
Japanese maples have to be grown in deep full shade.
They're understory trees, so they do best in dappled light or afternoon shade, but too much shade washes out the color and slackens the form. The real hazard in sun isn't the light itself, it's scorch on hot, dry, windy sites where the soil dries out. Filtered light with steady moisture beats deep shade every time.