Tree · Cupressaceae
Juniper
Juniperus chinensis
Give it full sun and sharp drainage, and juniper rewards you with a long, easy life and almost no upkeep.
Full sun
Every 7–14 days
USDA 3–9
1–59 ft · 0.3–18 m
Overview
Juniper is one of the toughest evergreens a gardener can put in the ground, and growing it feels genuinely satisfying. It belongs to the cypress family and ranges right across the northern hemisphere, brushing off cold, heat, drought, salt, and rough ground that would flatten most shrubs. The forms leap from flat groundcovers a foot high to upright trees reaching as tall as 59 feet (18 m), every one carrying that same aromatic, scale-like or needle-like foliage.
The real thrill is how much juniper gives back for how little it asks. Settle it into sun and free-draining soil and it holds its color through winter, locks down a slope, screens a fence line, or stands alone as a sculptural knockout. On female plants the berry-like blue cones ripen over about two years and pull birds in through the cold months, turning the plant into a living feeder.
One rule keeps the fun on track, so learn it early. Juniper grows slowly and will not resprout from bare old wood, which means the shape you build in the first years is the shape you keep for good. Prune a little and often to steer it, and never gamble on one hard cut to fix things later.
Care
The short version: full sun and fast-draining soil win the game outright. Water through the first year to lock in the roots, then step back and let it run, feed it rarely, and cut only into green growth.
Light
Juniper thrives in full sun, ideally 6 or more hours a day, and it will take a little partial sun in stride. Push it into real shade and the growth thins, the color drops off, and disease muscles in.
Water
Water a new juniper regularly through its first year to lock the roots in. After that it turns seriously drought tolerant and only wants help in a long dry spell, since the one thing it flat-out won't forgive is soggy soil.
Soil
Sharp drainage carries the day here, far more than rich ground. Juniper powers through sandy, rocky, and even clay soil as long as water keeps moving, and it stays happy across a wide pH of 5.0 to 8.0.
Temperature
Barely any shrub matches this range. Juniper takes everything from about -29°F to 100°F (-34°C to 38°C), gripping its foliage through brutal winters and shrugging off summer heat like it is nothing.
Humidity
Outdoor humidity is whatever it is, and juniper never blinks at it. Air movement carries far more weight than any humidity number, since still, damp air around crowded foliage throws the door open to the tip blights.
Feeding
Juniper barely asks to be fed. If growth looks weak, one light application of balanced or slow-release fertilizer in spring does the job, and piling on more just backfires.
Pruning
Shape it lightly in late spring and cut only into green growth, because bare old wood won't push new shoots and leaves a gap for keeps. Pick off dead, diseased, or blight-killed tips while the weather runs dry.
Repotting
Container and bonsai junipers want fresh room every 2 to 3 years. Repot the moment roots start circling the pot, water blasts straight through, or growth slows with yellowing foliage.
Size & spacing
The forms swing wildly, spanning 1 to 59 feet (0.3 to 18 m) in height, with spreads of 2 to 20 feet (60 cm to 6 m). Match the cultivar to the space and hand each plant room for air to move through the canopy.
When to plant
Juniper gets planted, not sown, and spring and fall are the windows to jump on, when the soil works easily and the weather stays mild. Set plants out then so the roots dig in before summer heat or winter cold arrives, and keep the water going through that first season while they take hold.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Plant: spring or fall
- Harvest: inconspicuous; blue berry-like female cones mature over about two years
Hardiness
USDA hardiness zones: 3–9
Temperature: down to -40°C
Troubleshooting
Site a juniper well and it powers through years trouble-free, so most hiccups trace straight back to wet soil or crowded, damp growth. Scan the new tips, the inner foliage, and the branches, and match what you spot below before you reach for a spray.
Whole plant thinning and sliding into decline
Park a juniper in wet ground and Phytophthora root rot moves in, thinning, dulling, and fading the foliage from the top down. The roots blacken and rot, and once it takes hold there is no quick rescue. Sharpen the drainage, dial back the water, and pull any plant that has slipped too far to bounce back.
Fix:
- Improve drainage and stop overwatering
- Plant in raised beds and amend heavy clay with porous material such as ground pine bark
- Remove severely affected plants, as root rot is difficult to reverse
New tips fading and dying back
Two fungal tip blights drive this, and both respond fast to good habits. Phomopsis tip blight jumps on soft new growth in warm, wet weather, and Kabatina tip blight hits year-old twigs in spring through small wounds. Grab your shears on a dry day, cut well below the dead tissue, wipe the blades between cuts, and open the plant up so air rushes through it.
Fix:
- Prune out and destroy blighted tips well below the dead tissue during dry weather, disinfecting tools between cuts
- Improve air circulation by spacing and selective thinning
- Avoid overhead watering and wetting foliage
- Apply a labeled fungicide (mancozeb, thiophanate-methyl, or copper) protectively on new growth where blight is recurring
Needles going stippled and yellow, with fine webbing
Two sap-feeders spark this look and both come off with a little effort. Spruce spider mites stipple the needles and string fine webbing through the cool of spring and fall, while juniper scale grips as tiny bumps and yellows the foliage. Tap a branch over white paper to catch the mites on the move, blast them off with a hard jet of water or insecticidal soap, and hit the scale with a dormant oil spray in late winter.
Fix:
- Dislodge mites with a strong spray of water
- Apply insecticidal soap or a labeled miticide for heavy mite infestations and preserve natural predators
- Apply 2-3 percent horticultural oil as a dormant spray in late winter for scale, or treat crawlers with a labeled insecticide
Spindle-shaped bags swinging from the branches
Those carrot-shaped bags belong to bagworms, caterpillars that munch away from inside a case they stitch together out of foliage. Let a big crop run and it can strip branches or drop a whole plant, so jump on them early. Pluck the bags off through fall and winter to wipe out the overwintering eggs, then hit the young larvae with Bt in spring while they are still small.
Fix:
- Handpick and destroy bags in fall and winter to remove overwintering eggs
- Apply Bacillus thuringiensis (Bt) in spring while larvae are young and small
- Use a labeled insecticide for heavy infestations of older larvae
Woody galls erupting orange horns in spring
Meet cedar-apple rust and its relatives, fungi that leap between junipers and apple-family plants like crabapple and hawthorn. The upside is that they barely scratch the juniper, so you act mostly to guard the fruit trees close by. Snip the woody galls out before they fire off their orange horns, and keep junipers well clear of apples and crabapples.
Fix:
- Prune out and remove woody galls before they produce orange horns in spring
- Plant rust-resistant juniper cultivars
- Do not plant junipers within a few hundred yards of apples, crabapples, or hawthorns
- Apply a labeled fungicide (mancozeb or propiconazole) where control is needed, though galls do little harm to the juniper itself
Toxicity
Juniper is an easygoing plant to grow around animals and people. It carries none of the toxins on the standard poison lists, and its sharp, bitter foliage usually keeps pets and livestock from eating much anyway. Just keep two things in mind: the berry-like cones can mildly upset a stomach in quantity, and only a few species are the true culinary juniper that flavors gin.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats Caution
Juniper carries no poison for cats, and that sharp, aromatic foliage sends most of them packing before they take a bite. A cat that does work through a pile of the berry-like cones might get a quick, mild stomach upset that clears on its own.
Dogs Caution
Dogs can dig and snuffle around a juniper with zero real risk, since it holds none of the listed toxins. Gulp down a mouthful of cones or oily foliage and the worst on the cards is a bit of drooling or a loose stool for a day.
Horses Caution
That punchy terpene scent makes juniper taste rough, so horses breeze right past it. One that grazes a big load of berries might get mild gut irritation, but the plant never rates as a poisoning risk.
Rabbits Caution
Rabbits rarely bite into the resinous needles, and juniper packs no toxin that threatens them. Keep any nibbling light, though, since the volatile oils can loosen the gut once a lot goes down.
Livestock Safe
Cattle, goats, and sheep march right past juniper thanks to its bitter, aromatic foliage, and it stays off the usual lists of plants that poison them.
Birds Safe
Birds dive into the ripe blue cones and haul the seed off as they go, so the fruit is pure upside for them.
People Edible with care
The berries of a select few species, mainly Juniperus communis, deliver the spice that flavors gin, but ornamental landscape junipers are not all edible and some cones can turn a stomach. Keep the kitchen to known culinary species, and pull on gloves for the prickly, oily foliage.
The aromatic foliage and berry-like cones may cause mild, self-limiting stomach upset if eaten in quantity, and the prickly juvenile needles plus juniper oils can mildly irritate skin, so wear gloves when pruning. This is irritation, not poisoning.
Varieties
Junipers explode into more forms than almost any other evergreen, from creeping mats to pencil-thin columns, so there is a fun fit for nearly any spot. These are the ones you will run into most at the nursery.
'Hetzii'
A powerhouse wide-spreading blue-green shrub that fills big foundation plantings and screens with ease.
'Sea Green'
A compact, fountain-shaped shrub whose arching branches and mint-green foliage make one of the easiest low hedges going.
'Spartan'
A narrow, dense, dark green column that shoots to about 15 to 20 feet tall but holds to only around 5 feet wide, the classic upright screen.
'Hollywood' / 'Kaizuka'
An irregular, twisting upright in rich green that begs to be grown as a living sculpture.
Juniperus scopulorum 'Skyrocket'
A pencil-thin blue-gray column so slim it shoots skyward as a vertical accent in the tightest spots.
Juniperus squamata 'Blue Star'
A dwarf mounding shrub of 1 to 3 feet, packed tight with dense silvery blue-gray needles.
How to propagate
Picking how to multiply a juniper comes down to what you want, since named cultivars never come true from seed and have to be cloned another way.
Stem cuttingsModerate
Late fall through winter from semi-hardwood to hardwood growth · Several weeks to a few months to root
Cuttings drive most cultivars because they keep the new plant true to the parent, which is half the fun of building a collection. Take semi-hardwood to hardwood pieces from late fall through winter, dip them in rooting hormone, and slot them into well-drained media, where they root over several weeks to a few months.
GraftingDemanding
Winter under glass · Weeks to months
Grafting unlocks the upright tree forms and choice cultivars that flat-out refuse to root from cuttings. Done in winter under glass, the union takes weeks to months to knit together, which is why it stays a project for skilled growers.
LayeringEasy
Spring · Several months to a year
Layering is the easiest win of the lot with the low, spreading kinds. Pin a trailing branch to the soil in spring and it roots right where it lands over several months to a year, a natural for groundcover and shrub forms.
SeedDemanding
After cleaning and cold stratification · Slow and erratic, often more than a year to germinate
Seed raises species rather than named cultivars, since those never come true from it. Clean the cones, give the seed a cold stratification, then settle in for the long game, because germination runs slow and erratic and often stretches past a year.
Myths
The berries on any landscape juniper are fair game to harvest and eat like the ones that flavor gin.
Only a handful of species, mainly Juniperus communis, get grown as a culinary spice. Plenty of ornamental junipers carry berry-like cones that taste rough and can trigger a mild stomach upset, so don't assume the berries on a landscape juniper are edible.
An overgrown juniper can be brought roaring back by cutting it hard into the old bare wood.
Junipers refuse to push new shoots from old leafless wood, so a hard cut into bare branches carves out a dead hole that stays for good. Always prune into green, foliage-bearing growth and take the plant back a little at a time.