Shrub · Adoxaceae
Viburnum
Viburnum
Give it sun, room, and a steady drink while young, and viburnum returns spring fragrance and fall berries for decades.
Full sun
Every 5–10 days
USDA 2–8
4–12 ft · 1.2–3.7 m
Overview
Viburnum is a deciduous shrub built for the long haul, and it earns its place with two seasons of show. Spring brings clusters of white or pink flowers, many of them sweetly fragrant, and fall follows with bright berries and burning leaf color. The genus runs deep, from low rounded mounds to plants that reach the size of a small tree.
What makes viburnum a beginner's friend is how little it asks. It shrugs off cold down to -40°F (-40°C), takes sun or part shade, and grows in clay, loam, or sand without complaint. Once its roots are down, most kinds ride out a dry spell on their own.
The berries are more than decoration. Songbirds strip them through fall, and the dense branching gives nesting cover, so a viburnum hedge pulls in wildlife as well as it screens a fence line. Plant it where you'll pass close in spring, and the fragrance pays you back every year.
Care
The short version: plant it in full sun to part shade in average, well-drained soil, keep it watered while it settles in, and prune right after the spring flowers fade.
Light
Viburnum does best in full sun, where it flowers hardest and fruits heaviest, but it also takes partial sun and partial shade. Push it into deep shade and you trade away both the bloom and the fall berry show.
Water
Give it consistently moist, well-drained soil, especially while it's getting established. Water deeply through the first season and during dry spells, every 5 to 10 days as the weather demands. Once the roots are settled, most viburnums handle drought on their own.
Soil
Average, medium-moisture loam suits it, and it tolerates clay or sand just as well. Aim for a slightly acidic to neutral pH of 5.5 to 7.0, and make sure water drains rather than pools around the roots.
Temperature
This is a cold-hardy shrub that takes winters down to -40°F (-40°C) and summer heat up to 95°F (35°C). That range covers most temperate gardens, so it rarely needs winter protection.
Humidity
Ordinary outdoor humidity is plenty, so there's no number to chase. What matters more is airflow, since crowded, damp leaves invite powdery mildew and leaf spot.
Feeding
Feed in early spring with a balanced slow-release or general shrub fertilizer. A viburnum in decent soil often needs little to no feeding at all, so don't overdo it.
Pruning
Prune right after the flowers fade, because the buds for next year form on old wood and a late cut removes them. Take out dead, damaged, or crossing stems and shape as you go. An old, overgrown plant will even tolerate hard rejuvenation pruning.
Repotting
Viburnum is a landscape shrub that rarely needs repotting. If you're holding one in a container, move it up only when you see roots circling the pot, poking out the drainage holes, or water running straight through.
Size & spacing
Expect a mature shrub from 4 to 12 feet (1.2 to 3.7 m) tall with a 4 to 10 foot (1.2 to 3 m) spread, depending on the species. Give each plant room to reach its full width so air moves freely and disease stays down.
When to plant
Viburnum sets its flower buds on old wood, so timing is about pruning more than planting. Set new shrubs out in spring or fall while the weather is mild, enjoy the bloom from March into May, and watch the berries color up from late summer into fall.
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: Spring (March to May); colorful berries ripen late summer into fall
Hardiness
USDA hardiness zones: 2–8
Temperature: down to -46°C
Troubleshooting
Most viburnum trouble shows up on the leaves, whether chewed by beetles or marked by a fungus or bacteria. Catch it early and the shrub recovers without much fuss. Match what you see below, then act before it spreads.
Leaves chewed down to the veins in spring
This is the viburnum leaf beetle, whose larvae and adults strip foliage until only the veins remain. Three hard years in a row can kill the shrub, so deal with it early. Cut out and burn the egg-laid twigs over winter, then treat the young larvae soon after they hatch in spring.
Fix:
- Prune out and destroy egg-infested twigs between October and April before larvae hatch
- Treat newly hatched larvae in spring with a labeled insecticide applied shortly after emergence
- Alternatively apply a single labeled systemic soil drench in spring but no later than early July to control adults
Angular dark spots on the leaves with some dieback
Sharp-edged dark blotches that spread in cool, wet spring weather point to bacterial leaf spot, while stressed shrubs can also lose shoots to a crown borer. The angular shape sets it apart from the rounder marks of a fungus. Pull and destroy the spotted leaves, prune out the worst shoots, and keep water off the foliage so the leaves dry fast.
Fix:
- Remove and destroy infected leaves and prune out badly affected shoots
- Avoid overhead watering and work plants only when dry
- Improve spacing and airflow to speed leaf drying
White powdery dust coating the upper leaves
That gray film is powdery mildew, a fungus that settles on crowded, shaded plants when days run warm and nights turn cool. It looks worse than it is and rarely does lasting harm. Open the shrub up with selective pruning and let in more sun, and reach for a labeled fungicide only if it spreads. Skip sulfur, since it injures sulfur-sensitive viburnums.
Fix:
- Improve air circulation by proper spacing and selective pruning
- Reduce excessive shade
- Apply a labeled fungicide such as myclobutanil, propiconazole, or thiophanate-methyl if needed; use horticultural oil only when temperatures stay below 85 degrees F
- Do not use sulfur, which can injure sulfur-sensitive viburnums
Toxicity
Viburnum is one of the safer shrubs to keep around a busy household. The ASPCA lists it as non-toxic to cats, dogs, and horses, and the berries feed birds rather than harm them. A pet that bolts a mouthful of leaves might have a brief upset stomach, but there's no real poison to worry about.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats None
Viburnum is safe for cats. A cat that nibbles a lot of leaves might drool or bring it back up, but that's the usual response to any greenery, not poisoning.
Dogs None
Dogs can be around viburnum without worry. Gulping down a pile of foliage or berries may upset the stomach for a short while, yet there's no real toxin at work.
Horses None
The shrub is non-toxic to horses, so a curious browse along the hedge does no harm.
Rabbits Safe
Rabbits can graze viburnum safely. The leaves and twigs carry nothing harmful, though a steady diet of any one plant is never ideal.
Livestock Safe
Cattle, goats, and sheep can browse the foliage without trouble, since none of it is poisonous to grazing animals.
Birds Safe
Birds flock to the ripe berries and eat them happily. The fruit feeds songbirds through fall and is one of the shrub's real strengths in the garden.
People Safe
Viburnum isn't dangerous to people. Eating a lot of raw fruit from some species can leave you with mild stomach upset, but it isn't seriously toxic.
Although not toxic, eating any plant material can cause mild, temporary stomach upset or vomiting in pets, and large quantities of raw fruit of some species may cause mild digestive upset in people.
Varieties
The genus holds hundreds of species and cultivars, far more than any one garden needs. A few stand out for fragrance, fruit, or toughness, and these are worth knowing by name.
Viburnum carlesii (Koreanspice viburnum)
A slow-growing 4 to 6 foot shrub whose pink buds open to fragrant white snowball clusters in early spring before turning to blue-black fall berries.
Viburnum dentatum (Arrowwood)
A tough native running 5 to 10 feet tall, with flat creamy-white flower heads, blue-black drupes the birds love, and reliable deer resistance.
Viburnum lentago (Nannyberry / Black Haw)
A tall native viburnum that the ASPCA confirms is non-toxic to cats, dogs, and horses.
Viburnum opulus (European cranberrybush)
A non-native carrying showy red fruit that has turned invasive in parts of the US, unlike the well-behaved native viburnums.
How to propagate
You can multiply viburnum three ways, from quick softwood cuttings to slow seed, and each suits a different goal and level of patience.
Stem cuttingsModerate
Late spring to early summer while growth is soft (softwood) · Roots in about 3-4 weeks under mist; transplantable plants in about 3 months
Softwood cuttings are the standard way to copy a named cultivar true to type. Take them in late spring to early summer while the growth is still soft, dip the cut end in rooting hormone, and keep them warm and humid. They root in about 3 to 4 weeks under mist and are ready to move on in roughly 3 months.
SeedDemanding
Sow fresh seed in fall outdoors · Often 1-2 years to germinate due to double dormancy
You can grow the straight species from seed, but it tests your patience. Sow fresh seed outdoors in fall and the double dormancy can hold it back for 1 to 2 years before it sprouts, often slow and erratic. Seed saved from a cultivar won't come true to the parent.
LayeringEasy
Spring to summer · Several months to a year to root
Layering is the easy route when a shrub carries low, flexible branches. Pin one down into the soil in spring or summer, leave it attached to the parent while it roots over several months to a year, then cut it free as its own plant.
Myths
Any single viburnum will set a heavy crop of berries on its own.
Most viburnums need a second, genetically different cultivar of the same species planted nearby to fruit well. Plant just one shrub and you often get few berries or none at all.
Viburnum berries are dangerously poisonous.
The ASPCA lists viburnum as non-toxic to cats, dogs, and horses. Eating a lot of the raw fruit of some species may leave a person with mild stomach upset, but the plant is not considered seriously toxic.