Tree · Cupressaceae
Japanese Cedar
Cryptomeria japonica
Give it rich, moist soil and shelter from winter wind, and Japanese cedar rockets into a towering evergreen spire.
Full sun
Every 7–14 days
USDA 5–9
50–70 ft · 15.2–21.3 m
Overview
Japanese cedar is the national tree of Japan, where it goes by sugi and marches down temple grounds in tall, stately rows. The name throws people, so let us clear it up fast. This tree belongs to the cypress and redwood family, not the true cedars, and it stands alone in its own genus. Out in the garden it comes across as a soft, feathery evergreen conifer, with awl-shaped needles that spiral around every shoot.
This tree brings serious presence to a yard. Turn it loose and it climbs to 50 to 70 feet (15 to 21 m) with a broad pyramidal crown, while the reddish-brown bark peels off in long, shaggy strips that pack the trunk with character. It laughs off cold down to -20°F (-29°C), which sends it cruising through USDA zones 5 to 9.
Most growers grab a named cultivar over the wild form, and the choices are a blast. Some hold tight as tidy dwarf globes for a small bed, while the full-size selections rip into fast, dense screens. Whatever the size, it just wants steady moisture and a spot out of the harshest wind, and from there it takes off and looks after itself.
Care
The short version: full sun to light shade, rich, moist, acidic, well-drained soil that never dries out, and a planting spot tucked away from harsh, drying winter wind.
Light
Japanese cedar hits its stride in full sun, where the canopy fills in dense and even. It will take partial sun or light shade too, but a shadier spot leaves the growth thinner and looser.
Water
Keep the soil consistently moist, above all while the tree is young, and never let it dry out. Watering every 7 to 14 days covers most settings, and an established tree shrugs off a brief dry spell. Push it into real drought, though, and it fights back.
Soil
Set it in rich, deep, moist, well-drained loam that leans acidic, ideally a pH of 5.0 to 6.5. You want soil that grips moisture without going waterlogged, so mix in organic matter on heavy or thin ground.
Temperature
This tree is built tough, hardy from -20°F to 100°F (-29°C to 38°C) across USDA zones 5 to 9. It powers through summer heat and deep winter cold alike, though drying winter wind bites harder than the cold ever does.
Humidity
Average outdoor humidity is all it takes, so skip tracking a number. Steady soil moisture drives the show far more than whatever the air is up to.
Feeding
Feed in spring with a balanced or acid-forming slow-release fertilizer made for evergreens. Once a season fuels a healthy tree, and piling on more only pumps out soft, weak growth.
Pruning
Japanese cedar barely needs pruning, and that is a win. Clip out any dead, damaged, or winter-burned shoots in spring, and you are usually done. It also shears like a dream, which is why it snaps into such a clean screen or hedge.
Repotting
Most Japanese cedars sink into the ground and never need repotting. Keep one in a container and you repot rarely, jumping in when roots circle the pot, water rushes straight through, or new growth stalls out.
Size & spacing
Plan for a tree that shoots to 50 to 70 feet (15 to 21 m) tall with a spread of 20 to 30 feet (6 to 9 m). Give it that much room from buildings and other trees, or drop down to a dwarf cultivar for a tighter spot.
When to plant
Japanese cedar is an evergreen conifer, so forget chasing a sowing window or timing a harvest, there is neither. Plant it in spring or early fall, while the soil runs warm and moisture holds, so the roots grab a full stretch of mild weather before heat or hard cold shows up.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Plant: Spring or early fall
- Harvest: Non-flowering; grown for evergreen foliage and form (cones mature in fall)
Hardiness
USDA hardiness zones: 5–9
Temperature: down to -29°C
Troubleshooting
Japanese cedar is an easy, low-maintenance tree, and the handful of problems it hits show up right in the foliage. Most are cosmetic and clear out with the season. Match what you spot below before you jump in to fix anything.
Winter foliage flips to bronze and looks scorched
Relax, because this is almost always winter bronzing, a normal seasonal color change that plenty of cultivars run through before they bounce right back to green in spring. It hits hardest on the windward side, where drying wind yanks moisture from the needles faster than frozen roots can pump it back. Tuck the tree out of that harsh wind, send it into winter with moist soil, and clip off any shoots that stubbornly stay brown once growth fires up again.
Fix:
- Site plants where they are sheltered from harsh, drying winter winds
- Keep soil adequately moist going into winter
- Prune out shoots that fail to green up in spring
Spotty needles and a touch of twig dieback
This usually traces back to leaf spot and leaf blight fungi like Cercospora and Pestalotiopsis, which move into the still, damp air down among the lower inner branches. They pounce on a tree that is already stressed, so a plant wrestling with a rough site or a dry spell is the one that grabs it. Good news though, the damage stays cosmetic, so snip out the marked twigs, open the canopy to get air moving, and keep the tree growing strong, and it powers right through.
Fix:
- Prune out and dispose of affected twigs and foliage
- Improve air circulation and avoid overhead wetting of foliage
- Maintain plant vigor with proper siting, water, and nutrition
Toxicity
Great news for pet owners: Japanese cedar is not toxic. It lands on no poison list, and animals live right alongside it without risk. The one thing to mind is the foliage itself, since the needles run stiff and sharply pointed.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats None
Cats can prowl around this tree all they like, since it packs no known toxin. Let one chew a bit of foliage and the worst it might get is some drooling or a quick stomach upset, just like any coarse plant.
Dogs None
Dogs roam near Japanese cedar with zero trouble, because it never shows up on a poison list. A pup that grabs a fallen sprig might catch a brief, mild bout of tummy upset and nothing beyond that.
Horses Safe
Horses have nothing to dread from this tree, since it poses no toxic threat. Those stiff, awl-shaped needles are prickly enough that most horses skip right past it anyway.
Rabbits Safe
Rabbits stay out of harm's way around this conifer, as no harmful compound has ever been logged in it. The prickly foliage barely tempts them to take a bite in the first place.
Livestock Safe
Cattle, goats, and sheep can graze right up to it with no poisoning risk at all. Those sharp, resinous needles make it a snack they would rather skip anyway.
Birds Safe
Birds take zero harm from the tree and love to duck into its thick evergreen cover for shelter. Nothing in the foliage or the cones can hurt them.
People Safe
Japanese cedar is safe to plant and handle, though the pointed needles can prick bare skin, so grab gloves for close work. It carries no edible part, so it earns its keep with shade and screening rather than anything for the plate.
Foliage is harmless to handle, though needles are sharply pointed and awl-shaped.
Varieties
The straight species gets big fast, so most growers grab a cultivar sized to the space. These are the ones you will run into most.
Yoshino
A vigorous, fast grower of about 30 to 40 feet whose blue-green foliage keeps its color right through winter with barely any bronzing.
Black Dragon
A punchy dwarf loaded with very dark green foliage on an upright, dense, slightly ragged pyramid.
Globosa Nana
A slow, rounded dwarf shrub of about 2 to 4 feet whose bluish-green needles flush a rusty-red cast once winter rolls in.
Sekkan-sugi
The showstopper grown for creamy-yellow new growth that lights up the branch tips.
Radicans
A fast, narrow pyramid in rich blue-green that races to become a favorite screen.
How to propagate
You can launch Japanese cedar from seed, cuttings, or layering, and the method comes down to whether you want a true copy of a named cultivar or simply more trees.
SeedModerate
Sow in fall or spring after cold stratification · Several months to germinate; years to reach landscape size
Kick off Japanese cedar from seed by giving it a cold stratification and sowing in fall or spring, then dig in for the wait, because germination stretches over several months and the trees need years to hit landscape size. Heads up, though: the seedlings come out variable, so named cultivars never breed true this way.
Stem cuttingsModerate
Semi-hardwood cuttings in late summer to fall · Several weeks to months to root
Chase an exact copy of a named cultivar and cuttings deliver every time. Snip semi-hardwood cuttings from late summer into fall, dip them in rooting hormone, and keep them humid while they push out roots over the following weeks to months.
LayeringModerate
Spring · One or more seasons
This one practically does itself, since low branches root wherever they hit the ground. Pin one down in spring, let it grow its own roots, and give it a season or more before you cut the new plant free.
Myths
Japanese cedar is a true cedar.
The name throws people off, but this tree shares zero kinship with the true cedars of the genus Cedrus. Cryptomeria claims its own genus within the cypress and redwood family, Cupressaceae. Read the common name as a quirk, not a clue to its family.