Shrub · Buxaceae
Common Boxwood
Buxus sempervirens
Slow, sturdy, and evergreen year-round, boxwood gives any clipped, formal garden its green backbone.
Full sun
Every 5–10 days
USDA 5–8
5–15 ft · 1.5–4.6 m
Overview
Boxwood is the shrub that hands a garden real structure, the kind that holds its shape clean through every season. This slow-growing evergreen shrub from the box family packs its branches dense, so it clips beautifully into a sharp hedge, a low edging, or a rounded ball that pins down a border. Let it run and it can hit 15 feet, but most growers keep it tighter and crisper than that, and shaping it is half the fun.
Growing boxwood pays off for anyone willing to play the long game. It puts on just a little each year, so a full hedge stands for seasons of steady progress rather than an instant screen, and watching it fill in becomes its own quiet reward. Stick with it and you get a shrub that thrives in deep shade to full sun, powers through cold down to zone 5, and keeps going strong for decades once it digs in.
Boxwood does throw a few real challenges your way, and meeting them head-on keeps a planting thriving. Boxwood blight can defoliate a plant in days, leafminers and mites chew up the leaves, and soggy roots invite rot. Site it smart, keep the bed spotless, and open up space for air to move, and you shut most of those problems out before they ever start.
Care
The short version: boxwood takes on anything from full sun to full shade, thrives in evenly moist but well-drained loam, and grows slowly enough that one clean shaping after the last spring frost keeps it looking sharp all season.
Light
Boxwood plays it cool with light, taking on anything from full sun to full shade. It packs in densest under sun, and the one thing to dodge is full winter sun on an exposed site, which scorches the evergreen leaves brown.
Water
Keep the soil evenly moist but never soggy, which usually means a drink every 5 to 10 days once it is established. The roots ride shallow, so pile on 1 to 2 inches of organic mulch to lock in moisture, and steer clear of digging around the base. Overwatering and poor drainage are what kick off root rot.
Soil
Set boxwood in well-drained loam that holds even moisture and it takes right off. It stays easy about pH, thriving anywhere from 6.0 to 8.0, so slightly acidic straight through to slightly alkaline ground all works. The one soil to fix or skip is heavy, waterlogged clay.
Temperature
Boxwood powers through a huge range, hardy from about -20°F to 100°F (-29°C to 38°C). The real threat is not the thermometer but exposure, since drying winter wind and sun hit harder than cold ever does.
Humidity
Everyday outdoor humidity does the job, so skip chasing any number. Air movement counts for way more, because still, damp air in a crowded planting hands blight and other fungal diseases exactly what they want.
Feeding
A balanced fertilizer in spring keeps boxwood charging through the year. Team that yearly feeding with solid mulch and the plant holds its color and density without a single fancy step.
Pruning
Shape boxwood after the last spring frost and never before, or you shove tender growth right into a late freeze. Snip out dead or diseased branches the second you spot them, and rake out leaves wedged in the branch crotches, since trapped debris hands disease its first foothold.
Repotting
Boxwood is rarely repotted and would rather you leave it be once it is cruising along. In a container, keep watch for roots circling the pot, water shooting straight through, or growth that stalls, and bump it up a size only when those signs show.
Size & spacing
Plants stretch 5 to 15 feet (1.5 to 4.5 m) tall and roughly as wide, though clipping keeps most far tighter. Hand a hedge the room its mature spread demands so air whips freely between plants and disease struggles to grab hold.
When to plant
Get boxwood into the ground in spring or early fall, when the soil works easily and the weather plays nice. Stake out a spot sheltered from harsh wind and full winter sun, and hand the roots a full season to dig in before summer heat or deep cold rolls through.
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, in a site sheltered from strong winds and full winter sun
- Harvest: April to May (greenish-cream, insignificant flowers)
Hardiness
USDA hardiness zones: 5–8
Temperature: down to -29°C
Troubleshooting
Boxwood powers along trouble-free for years, then drops its short list of weak spots on you all at once. Most of what goes sideways turns up in the leaves, from fast browning and leaf drop to blisters and a dull stippled cast, while the nastiest trouble kicks off out of sight at the roots. Track your symptom down below and jump on it early, because the serious diseases simply will not be cured.
Brown leaf spots, fast leaf drop, and dark stem cankers
This points hard at boxwood blight, a fast-moving fungus that can strip a plant bare within days, though Volutella blight can pile on after winter injury with similar damage. Once it grabs hold there is no cure, so move fast. Cut out and bag the diseased stems, rake up every fallen leaf, lay down fresh mulch, and shield what is left with a chlorothalonil fungicide.
Fix:
- Remove and bag diseased stems and rake up all fallen foliage
- Apply fresh mulch over the soil surface
- Apply chlorothalonil, or chlorothalonil mixed with thiophanate methyl, fungicide
Yellowing foliage over rotted roots and peeling crown bark
When a whole plant slides from green to yellow and the roots pull up dark and mushy, that is Phytophthora root rot parked in wet, poorly drained soil. Check the crown, where the bark peels away once it is infected. No spray digs you out of this one, so fix the drainage, amend heavy clay, or shift the plant to a raised bed and back off the water.
Fix:
- Improve soil drainage
- Amend heavy clay soils or plant in raised beds
- Avoid overwatering
Swollen, blistered leaves splashed with yellow
Those raised blisters are the calling card of the boxwood leafminer, whose larvae feed inside the leaf. Split a blistered leaf open and the orange maggots sit right there in the mine. Stay alert for the adult flies from mid-April into early May, then hit them with a foliar spray of acephate or spinosad, or a soil drench of imidacloprid.
Fix:
- Apply acephate or spinosad foliar spray to larvae in mines
- Use malathion contact spray against adults
- Apply soil-applied dinotefuran or imidacloprid
Dull, silvery, stippled leaves
Fine yellow scratches and a flat silvery cast flag the boxwood mite. Tap a branch over a sheet of white paper and the tiny mites scramble across it for you to spot. Drive them back with horticultural oil at 1 to 2 percent or insecticidal soap, and keep stressed plants out of hot, baking sun, where mites multiply fastest.
Fix:
- Apply horticultural oil at 1-2 percent to kill eggs and adults
- Apply insecticidal soap
- Apply tau-fluvalinate miticide if needed
Cupped new leaves wrapped in white waxy fluff
The boxwood psyllid drains sap from the new growth and leaves it curled and cupped. Pry open the distorted shoots and small pale-green nymphs sit tucked under a white waxy coating. The damage runs mostly cosmetic, so leave light cases be and reach for acephate only when an infestation really takes off.
Fix:
- Treat only heavy infestations
- Apply acephate foliar spray
- Apply soil-applied dinotefuran or imidacloprid
Brownish-yellow foliage in late winter
Boxwood parked in open winter sun and drying wind often picks up a dull brownish-yellow cast called winter bronzing. It looks rough but rarely hurts the plant, and the fresh spring growth usually charges back a healthy green. Move plants somewhere sheltered from wind and harsh winter sun, water them well in fall, and pile mulch over the shallow roots.
Fix:
- Site or transplant plants where they are sheltered from winter wind and full winter sun
- Ensure adequate fall soil moisture before winter
- Apply organic mulch to protect shallow roots
Toxicity
Boxwood is toxic, so keep every part of it off the menu. The leaves and stems pack steroidal alkaloids, chiefly buxine, that set off vomiting and diarrhea in pets and people, and big amounts can drive seizures or respiratory failure in horses and livestock. The sharp bitter taste does most growers a favor by stopping animals before they swallow much, but stay smart and keep pets, grazing stock, and children clear of the foliage and any prunings.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds · People
Cats Moderate
A cat that chews the leaves usually drools and then vomits, with diarrhea right on its heels. The bitter taste tends to stop most cats before they eat enough to do real harm.
Dogs Moderate
Vomiting and diarrhea show up soon after a dog nibbles the foliage or chews on fallen prunings. Rake clippings up and keep them out of reach during a trim.
Horses Severe
Horses take the hardest hit. The alkaloids can bring on colic, diarrhea, seizures, and in large amounts respiratory failure, so keep boxwood and its trimmings well away from any paddock.
Rabbits Toxic
The same buxine that sickens other animals makes boxwood unsafe for rabbits. Never offer the leaves or stems, and fence the shrubs off from any free-ranging bunny.
Livestock Severe
Cattle, goats, and sheep can run into serious digestive and respiratory trouble from the foliage, and heavy grazing has proven fatal. Bitter leaves deter most stock, but hungry animals will still try them.
Birds Toxic
No part of boxwood is safe for birds to eat. Keep poultry and pet birds from pecking at the leaves or scattered clippings.
People Caution
No part of boxwood is edible, and eating the leaves or stems can cause vomiting and diarrhea. The sap also irritates sensitive skin, so wear gloves when you prune and keep curious children away.
Sap can cause contact dermatitis in sensitive people; wear gloves when pruning.
Helpline numbers
United States
ASPCA Animal Poison Control: (888) 426-4435 (fee applies)
Poison Control: (800) 222-1222
Canada
Poison Centres: 1-844-764-7669
Varieties
Boxwood ranges all the way from low spreading mounds to slim upright columns, and a handful of cultivars are well worth knowing by name for their shape or their knack for shrugging off pests.
Vardar Valley
A low, spreading form that tops out around 2 to 3 feet with bluish leaves, and it shrugs right off the boxwood leafminer that plagues other types.
Suffruticosa
The classic English boxwood, a dense, fragrant dwarf that creeps along painfully slowly and, for all its charm, fends off leafminers the worst of any cultivar.
Dee Runk
A narrow column that shoots up to about 8 feet tall while holding to just 2.5 feet wide, a natural pick for a tight vertical accent.
Elegantissima
A variegated cultivar that growers prize for the creamy-white edges ringing every leaf.
How to propagate
Boxwood takes its time but propagates reliably, and striking cuttings is the surest route to a true copy of a plant you already love.
Stem cuttingsModerate
Mid-July to early fall (semi-hardwood, current season's growth) · Several weeks to a few months to root
Boxwood roots readily from cuttings as long as you hand it some time. Take semi-hardwood pieces of the current season's growth from mid-July into early fall, grab only healthy, disease-free plants, and keep the cuttings moist and shaded while you work. Rooting takes its sweet time, running anywhere from several weeks to a few months, and hardwood cuttings strike just as well.
Myths
Boxwood is safe around pets since it is just a common landscape hedge.
Every part of the plant packs alkaloids that are toxic to dogs, cats, and horses. A pet that chews the foliage gets vomiting and diarrhea, and horses can react far worse. Being a familiar hedge doesn't make it safe to eat.
A spray will cure boxwood blight once a plant is infected.
Nothing cures the disease once it is in the plant. Boxwood blight can only be managed, never reversed, by cutting out infected material, keeping the area spotless, and using protective fungicides to slow it from spreading to healthy plants.