Shrub · Rosaceae
Common Ninebark
Physocarpus opulifolius
An easygoing native shrub with peeling bark and colorful leaves that barely asks for a thing.
Full sun
Every 7–14 days
USDA 2–8
5–8 ft · 1.5–2.4 m
Overview
Ninebark is about as easy as shrubs get. It's a rose-family native from eastern North America, and it takes cold all the way down to zone 2, handles drought once it's rooted in, and grows in just about any soil you've got. Where's the name from? That bark that peels off in thin papery strips, which gives the older stems a nice bit of texture right through winter.
These days, though, most folks grow it for the leaves. Breeders have come up with cultivars in deep purple, gold, copper, and wine-red, and little clusters of white-to-pink flowers show up in late spring too. On the dark and gold ones, the foliage keeps the show going from the day it opens until it drops in fall.
It's a fast, vigorous shrub, so it wants room and plenty of sun. Give it a bright spot where air moves and it pretty much looks after itself, but wedge it into damp shade and powdery mildew will find it. Get the spot right and you've got yourself a low-care backbone shrub that'll earn its keep for years.
Care
The short version: full sun gets you the best leaf color, average well-drained soil is fine since it adapts to whatever's there, and you only really need to water through that first season. After that it's drought tough, barely wants feeding, and just needs one prune a year right after it blooms.
Light
Ninebark does its best in full sun, and honestly the purple and gold cultivars hold their color way better there. It'll cope with partial shade, but you'll get duller leaves and a better chance of powdery mildew once the air stops moving.
Water
Water a new plant regularly through its first growing season so the roots can settle in. After that it's really drought tolerant and only wants a drink during a long dry stretch. Let the top half of the soil dry out between waterings, which usually lands around every 7 to 14 days.
Soil
This shrub isn't picky about its dirt at all. It's happiest in average, well-drained soil, but it'll adapt to clay, loam, sand, rocky, dry, and even wet spots. It handles a wide pH from 5.5 to 8.0, so most gardens work as-is without any amending.
Temperature
Ninebark is seriously hardy, shrugging off winter cold down to about -51°F (-46°C) and summer heat up to 100°F (38°C). That covers hardiness zones 2 through 8, which is exactly why it shows up in so many cold-climate gardens.
Humidity
Outdoor humidity isn't a thing to worry about on its own, so there's no number to aim for. What really matters is airflow, because crowded, stagnant air is what invites powdery mildew onto the leaves.
Feeding
This tough native barely needs feeding. If the growth looks weak, give it a light application of balanced fertilizer in early spring and leave it there. Too much, especially nitrogen, just pushes soft growth that fireblight loves to jump on.
Pruning
Prune right after it blooms and no later than mid-August, because next year's flowers form on old wood, and a late cut takes them off. Got an overgrown, leggy one? You can cut it close to the ground in winter and let it come back fresh.
Repotting
Ninebark belongs in the ground and hardly ever needs potting on. If you do keep one in a container, move it up when the roots circle the pot, poke out the drainage holes, or water starts running straight through.
Size & spacing
Plan for a good-sized shrub, 5 to 8 feet (152 to 244 cm) tall with a spread of 4 to 6 feet (122 to 183 cm). Give it that full width so air can move through the branches, and mildew gets less of a foothold.
When to plant
Ninebark's a hardy shrub, so you've got a nice wide window to plant it. Pop new plants in during spring or fall while the weather's mild, then keep an eye out for the white-to-pink flowers in late spring, around April through June, before the colored foliage takes the wheel for the rest of the year.
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: Late spring (April to June)
Hardiness
USDA hardiness zones: 2–8
Temperature: down to -46°C
Troubleshooting
Ninebark doesn't cause much fuss, and when something does crop up it's usually on the leaves rather than the whole plant. Most of it comes back to crowding and damp, still air. Find what matches below and jump on it before it spreads.
Shoot tips going black and hooking over like they've been burned
This one's fireblight, a bacterial infection that blackens the tips and curls them into a little shepherd's crook while they stay clamped to the branch. Here's the plan: cut the blighted wood out well below where the damage shows, wipe your tools clean between every cut, and burn or bin what you take off instead of composting it. Go easy on the nitrogen and prune when it's dry, and it usually stays away.
Fix:
- Prune out blighted wood well below visible damage
- Disinfect pruning tools between cuts
- Destroy removed material; do not compost
A white, dusty film settling over the leaves and shoot tips
That's powdery mildew, a fungus that loves still air and shade, and it tends to go after the dark-leaved cultivars first. So what fixes it? Thin out the crowded stems so air can actually move, pull off the leaves that look worst, and get the shrub into more sun. It looks pretty ugly, but it rarely does any real damage.
Fix:
- Improve air circulation by thinning crowded stems
- Remove and dispose of badly infected foliage
- Site or move plants into full sun
Dark little spots and blotches showing up across the leaves
Those are fungal leaf spots, and they show up when the leaves stay wet and the plants are packed too close together. They mess with the look of the shrub, but they hardly ever touch its health. Just rake up the fallen leaves, open things up so air can get through, and water down at the base instead of over the top.
Fix:
- Rake up and dispose of fallen infected leaves
- Improve spacing and airflow
- Avoid wetting foliage when watering
Toxicity
Nothing to stress about here. Ninebark isn't on the ASPCA poison lists and it's treated as non-toxic to pets, livestock, and people alike. About the worst a big mouthful could do is a quick, mild upset stomach, same as overdoing it on any leafy plant.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats None
Good news for cat people: ninebark is safe, and it doesn't show up on the ASPCA poison list. If a cat has a nibble, the worst you'll probably see is a bit of drool or a quick upset stomach, which is what happens with any leafy plant.
Dogs None
Dogs can hang out in the same garden as ninebark, no problem. Sure, if one scarfs down a big mouthful of leaves it might have a loose stomach for the afternoon, but there's no actual poison here to worry about.
Horses Safe
Horses grazing next to a ninebark hedge are totally fine. There's no toxin in it that would hurt them, and honestly they usually ignore the woody stems anyway.
Rabbits Safe
Rabbits, whether they're pets or wild, don't take any harm from ninebark. They'll often nibble the young shoots, and the leaves go down just fine.
Livestock Safe
Cattle, goats, and sheep can graze around ninebark without any issue, since there's nothing in it that would poison them. A goat might strip the soft new growth and be perfectly okay.
Birds Safe
Birds have nothing to fear from ninebark. Plenty of them feed on the dry seed capsules over winter and build nests in the thick branches, since it makes such good shelter.
People Safe
Ninebark isn't a poisoning risk for people either. It's not something you'd grow to eat, so there's no reason to taste it, but a stray bite won't hurt you.
No special handling precautions are required; wear gloves when pruning if you have sensitive skin.
Varieties
Most ninebark you'll spot for sale is a colored-leaf cultivar, not the plain green species. Here are the ones you're most likely to run into, grouped by the foliage they're grown for.
Diabolo
This is the famous dark one, with deep purple leaves that can drift toward green when a summer gets really hot.
Dart's Gold
It's all about those bright golden-yellow leaves, and they keep their color best when the shrub sits in full sun.
Summer Wine
Short on space? This compact one pairs dark wine-red foliage with white-to-pink flowers.
Coppertina
Its new growth comes in a coppery orange, then eases into red once the leaves grow up a bit.
Amber Jubilee
The leaves go through gold, orange, and amber, changing up their tones as the season rolls along.
How to propagate
There are three ways to make more ninebark, and which one you go with really just comes down to whether you care about keeping a cultivar's leaf color true.
Stem cuttingsEasy
Late spring to summer using softwood cuttings · 4 to 8 weeks to root
Want a named colored-leaf cultivar to come back looking exactly like its parent? Then cuttings are the way. Grab softwood or semi-hardwood pieces from late spring into summer, and they'll root in 4 to 8 weeks. Out of the three options, this one's the most dependable.
SeedModerate
Sow in fall or after cold stratification in spring · Several weeks to germinate; seedlings of cultivars vary
Seed works great for the wild species, either sown in fall or given a cold spell before you sow in spring, and it'll sprout over several weeks. Just remember, seedlings from a colored cultivar won't match the parent's leaves, so it's a bit of a gamble if you're after that color.
LayeringEasy
Spring through summer · One growing season
Layering couldn't be easier. Take one of those low arching branches, pin it down onto the soil anytime from spring through summer, give it one growing season to root, then cut it free from the parent as its own new plant.
Myths
The name ninebark means the bark peels off in exactly nine separate layers.
The name's really just pointing at that showy bark peeling off in thin strips down the stems, not counting anything. Nine here is an old figure of speech, a way of saying lots of layers rather than exactly nine.