Tree · Sapindaceae
Tamukeyama Japanese Maple
Acer palmatum
Feathery, deeply cut leaves in deep purple-red, spilling from weeping branches until they blaze scarlet in fall.
Partial shade
Every 3–7 days
USDA 5–8
6–8 ft · 1.8–2.4 m
Overview
Up close, the leaves are the whole story. Each one is cut almost to the midrib into slender, pointed lobes, so finely divided that the foliage reads as a soft, feathery lace rather than a solid blade. The color arrives deep and saturated, a purple-red that holds from the moment the leaves unfurl. The plant itself stays low, 6 to 8 feet (183 to 244 cm) tall and wider than it is high, its branches bending down into a dense, cascading mound of that fine-cut foliage.
The color is what sets this laceleaf apart from its kin. Where weaker forms slide toward a dull bronze in the heat, these leaves stay a rich, unfaded purple-red deep into summer. Growth is slow, and the leaves keep their fine, thread-like cut. When autumn comes the whole cascade catches fire, the dissected leaves shifting to scarlet and bright red before they let go.
For all the drama in the leaves, the flowers barely register: small, reddish-purple clusters that open in April and are easy to miss against the emerging foliage. The real presence comes from form and texture, the way the thin branches arch outward and down, layering the fine leaves into a low mound. When the site turns hot and dry, that same delicate cutting is what suffers first, the narrow leaf margins browning and crisping at the edges.
Care
The short version: those fine leaves keep their color and texture in part shade out of hot afternoon sun, in evenly moist, slightly acidic soil, over mulch-cooled roots, with only light shaping while the branches are bare and dormant.
Light
The fine leaves hold their color and stay intact in dappled or part shade, out of the hardest afternoon sun. In cooler regions they take full sun without harm as long as the soil stays moist. Under hot, dry, direct sun the thin, cut margins scorch and brown.
Water
The soil stays evenly moist, generally watered every 3 to 7 days and more through a heat wave. The finely divided leaves, with so much edge exposed, brown quickly once the roots dry. A layer of mulch holds water in the ground and keeps the roots cool.
Soil
Roots run best in moist, rich, well-drained loam on the acidic side, at a pH of 5.5 to 6.5. In soil too alkaline the leaves lose their depth of color and pale to a yellow chlorosis as iron is locked away. Plenty of organic matter suits it, limy ground does not.
Temperature
The wood is hardy across a wide span, from -20°F to 95°F (-29°C to 35°C), over USDA zones 5 through 8. Hard winter cold does the bare branches no harm. It is the warm extreme, where heat and sun press on the thin leaves, that leaves a mark.
Humidity
Everyday outdoor air is enough, so there is no humidity figure to hit. What keeps the delicate leaves whole is moist roots and cover from drying wind, far more than any moisture in the air itself.
Feeding
A single feeding of balanced slow-release fertilizer in early spring is plenty. Japanese maples take little, and too much pushes out soft, watery growth whose thin leaves scorch even sooner.
Pruning
The cascading shape needs only light pruning to hold its lines. Cut from late fall through midwinter while the branches are bare and dormant, since a wound opened in spring or summer weeps sap.
Repotting
A potted tree is moved up every 2 to 3 years, in late winter while it is dormant. Roots circling the pot, growth that stalls into smaller leaves, and water running straight through mark the time to repot.
Size & spacing
At maturity it stands 6 to 8 feet (183 to 244 cm) with a broader 8 to 12 feet (2.4 to 3.7 m) spread, the branches reaching wide to cascade. Slow growth means the tree fills that frame only over many years.
When to plant
This is a slow, long-lived tree that goes in once and stays put, so timing bows to placement. Set it out in spring or fall, after hard frost has passed, while the weather is mild enough for the roots to take hold before the leaves face their first summer or the bare branches meet deep 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, after frost danger has passed.
- Harvest: Insignificant reddish-purple flowers in April; grown for foliage with scarlet to bright red fall color.
Hardiness
USDA hardiness zones: 5–8
Temperature: down to -29°C
Troubleshooting
Because this maple lives and dies by its foliage, that is where trouble first shows: browned, curling edges on those fine leaves through summer. Most of what you see traces to the spot the tree sits in and how moist its roots stay. Match the look of the leaves below, then correct the placement or watering.
One-sided dieback with wilting, fading leaves
When the leaves on one side of the tree fade, wilt, and drop while branches die back, the cause is often verticillium wilt, a fungus in the soil that seals off its water-conducting wood from within. Peel back the bark of a wilting branch and the wood shows dark streaks running with the grain, a sample of which a diagnostic lab can confirm. There is no cure, so the dead wood comes out, the tree is kept vigorous with water and slow-release feed, and no susceptible species goes back into that ground.
Fix:
- Prune out dead and dying wood
- Maintain vigor with proper irrigation and slow-release fertilizer
- Consult a certified arborist for hazard assessment
- Remove severely affected plants and avoid replanting susceptible species in infested soil
Brown, crisping edges on the fine cut leaves
The browning starts at the very tips and margins of the leaves and is leaf scorch, worst on the foliage taking the most sun and wind. With each leaf sliced into thin lobes, there is little tissue to hold moisture, so the edges dry and crisp once the soil goes dry or the afternoon sun turns fierce. Afternoon shade, evenly moist roots, and a cooling layer of mulch bring it back under control.
Fix:
- Provide afternoon shade
- Keep soil consistently moist
- Apply mulch to retain moisture and cool roots
- Shelter from drying winds
Sticky, shining leaves under a black sooty film
A wet, glistening stickiness across the leaves is honeydew, secreted by aphids or scale as they feed on the sap, and the sooty black film spreading over it is a mold living on those sugars. The insects cluster on the undersides of the leaves and along the stems. A hard spray of water knocks the aphids loose, and horticultural oil or insecticidal soap clears a heavier infestation.
Fix:
- Hose off aphids with a strong stream of water
- Treat heavy infestations with horticultural oil or insecticidal soap
- Encourage beneficial predators
Toxicity
Nothing about this tree, from its cut leaves to its small flowers, holds a toxin: it is safe around animals. Acer palmatum is absent from ASPCA toxic-plant lists, and unlike red and silver maple, whose wilted leaves can poison horses, it carries no such danger. It can grow near cats, dogs, horses, and other animals freely.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats Safe
There is no toxin in the cut leaves for a cat to fear, and Japanese maple is not on the ASPCA toxic list. A tasted leaf does nothing. A large mouthful of any plant may bring brief drooling or a mild upset stomach.
Dogs Safe
A dog runs no risk from this tree, whose foliage holds nothing harmful. The most a heavy chewer would show is mild, passing stomach upset after eating many leaves at once.
Horses Safe
The maple that endangers horses is the red and silver kind, whose wilted leaves break down red blood cells. Japanese maple has no part in that, and stands safe around horses.
Rabbits Safe
No part of this tree would poison a rabbit. Its leaves are not a natural food, though, so any nibbling should stay light, with hay and fresh greens doing the feeding.
Livestock Safe
Goats, sheep, and cattle can graze beside a Japanese maple in safety, since it holds none of the maple toxins that reach horses.
Birds Safe
Birds come to no harm from the tree. Many settle in to perch and shelter among its arching branches.
People Safe
The tree is not poisonous to people. Nothing on it is grown to eat, but a leaf tasted by a curious child causes no harm.
No special handling required; minor stomach upset is possible if pets chew large amounts of any plant material.
Varieties
Tamukeyama shares its finely cut looks with a handful of other weeping laceleaf maples, and telling them apart comes down to color and habit. These are the closest look-alikes.
Tamukeyama
A heat-tolerant weeping laceleaf whose deeply cut leaves run purple-red into summer, then deepen to bright red in fall.
Crimson Queen
A weeping cutleaf whose finely dissected leaves stay a deep crimson through the summer.
Dissectum Atropurpureum
The old red-purple laceleaf, its foliage borne low in a weeping, rounded mound.
Seiryu
An upright cutleaf that trades the low red mound for a taller frame and leaves that stay green through summer.
How to propagate
The look of this cultivar cannot be raised from seed. Tamukeyama stays true to its cut leaves and deep color only through grafting, which is skilled nursery work.
GraftingDemanding
Late winter to early spring while dormant. · 1-2 years for the graft union to establish.
Tamukeyama does not come true from seed, so its cut leaves and deep color are carried on by grafting alone. A nursery unites a scion with Acer palmatum seedling rootstock through the dormant weeks of late winter and early spring, work that asks for a precise, steady hand. The graft then needs a year or two to knit before the young tree is ready to plant out.
Myths
Japanese maples are poisonous to cats and dogs.
There is no poison in these cut leaves. Acer palmatum is not on the ASPCA toxic list and is safe around cats and dogs. The danger people remember comes from red maple, a separate species, and it is that tree's wilted leaves that harm horses, not these.
Japanese maples have to grow in deep shade.
Not true. These maples grow from full sun to part shade. In hot climates the fine leaves simply need afternoon shade and steady moisture to stay whole and keep from scorching, which is a long way from the deep, dark shade the myth calls for.