Houseplant · Lamiaceae
Coleus
Coleus scutellarioides
Coleus is all about those bold, painted leaves, and it will brighten a shady corner or a sunny bed without asking much of you.
Bright indirect
USDA 10–11
0–3 ft · 0.2–0.9 m
Overview
Coleus is one of those plants you grow for the leaves, and what leaves they are, splashed with greens, reds, purples, and gold in patterns no flower really competes with. It is part of the mint family, with roots back in the tropics of Southeast Asia and northern Australia. It only toughs out winter outdoors in the warmest zones, but pop it in a pot or a windowsill and it is happy just about anywhere.
Here is the nice thing: it is fast and forgiving, so it is a great pick if you are still finding your feet. Pinch the tips every so often and it bushes out instead of going tall and leggy. The older types want shade and will bleach in hot sun, while newer ones like Wasabi and Pineapple shrug off full sun and keep their color, so where it goes really just depends on which one you have.
Technically coleus is a tender perennial, but most folks just treat it as an annual since the first frost finishes it off. Want to keep yours going? Cuttings root so easily you can overwinter a plant on a windowsill and set it back out in spring. Let it flower, though, and it starts to fade, so really the only chore is pinching off the bloom spikes to keep those leaves looking their best.
Care
The short version: figure out whether your coleus is a sun or shade type, then give it bright indirect light indoors or the right sun-shade mix outside, keep the soil lightly moist so it never dries out or sits soggy, and pinch the tips often to keep it nice and bushy.
Light
Indoors, coleus wants bright indirect light, and outside it all depends on your cultivar. Shade-preferring types are fine in part shade to full shade and will bleach in hot sun, while sun-tolerant ones hold their color out in the open. Give any of them too little light, though, and they get leggy and washed out.
Water
Keep the soil lightly moist all the time, so never let it dry out, but do not leave it sitting soggy either. Water when the top inch feels dry, and keep in mind that plants in pots dry out faster, so they will want it more often. Overdo it and you stunt the growth and damage the leaves, so let the extra drain away.
Soil
Go with moist, rich, loose soil that drains well and has plenty of organic matter mixed in. That kind of mix holds the steady moisture coleus likes while still letting water through, which keeps the roots from sitting wet and rotting.
Temperature
Coleus is a warm-weather tropical at heart, so it wants to stay above 50°F (10°C). It has zero tolerance for cold, and the first frost kills it flat out, so bring your containers in well before things turn chilly.
Humidity
Regular household humidity is plenty, so there is no number to fuss over here. What matters more is good airflow, because still, damp air around crowded plants is exactly what invites downy mildew and other leaf trouble.
Feeding
Feed it through the growing season, spring into summer, with a balanced bedding-plant fertilizer. A foliage formula like 24-8-16 beats a high-phosphorus bloom feed, which honestly just makes the plant stretch out and get leggy.
Pruning
Pinch those stem tips often to get it branching and keep it bushy and compact. And cut off the flower spikes as soon as they pop up in late summer, since letting it bloom and set seed makes coleus lose steam and go downhill.
Repotting
Repot whenever it needs it if you are growing coleus as a houseplant or in pots, and pot up your rooted cuttings as they take. Seeing roots circling or sneaking out the drainage holes, water rushing straight through, or growth slowing down? Those all mean it is time for a bigger pot.
Size & spacing
Coleus runs anywhere from 6 to 36 inches (15 to 91 cm) tall, with a spread to match, depending on the cultivar and how much you pinch it. Pinch it regularly and it stays fuller and more compact than it would if you just left it alone.
Troubleshooting
Most coleus problems boil down to just two things: the light is wrong for that particular cultivar, or the watering has gone too dry or too wet. The good part is the leaves and stems usually show you what is going on, so you can catch it early. Find your plant's symptom below and you will know what to do next.
Stems turning black and toppling after a frosty night
Coleus is a tender tropical, and the first frost kills it outright, blackening the stems and toppling the whole plant. There is no saving a frosted plant, so just toss it. But if you want to keep a favorite going, take stem cuttings or pot it up and bring it indoors before the cold hits, since it only survives outdoors in USDA zones 10 to 11.
Fix:
- Take stem cuttings or dig and pot favorite plants before frost to overwinter indoors
- Move containers indoors before cold weather
- Discard frost-killed plants
Stunted growth and rot from soggy soil
Coleus likes steady moisture, sure, but soil that stays waterlogged brings on root and stem rot. You will see the roots turn brown and mushy, the base of the stems go soft, and growth just stall out. So ease off the watering, make sure the pot or bed drains freely, and keep the soil lightly moist rather than soaked.
Fix:
- Reduce watering and let excess drain away
- Ensure pots and beds have excellent drainage
- Avoid wetting foliage when watering
Brownish angular blotches with leaves dropping and stunted growth
If you are seeing yellowing, angular brown blotches, curling leaves, and dropped foliage, that is downy mildew. Flip a leaf over and look for white, purple, or gray fuzz on the underside only, which sometimes takes a hand lens to spot. It loves temperatures between 60°F and 80°F (16°C to 27°C) once humidity climbs over 85%, so bag and bin the infected leaves, open the plant up for airflow, and water at the base to keep the leaves dry.
Fix:
- Remove and discard infected material in the trash, not compost
- Improve air circulation by spacing, thinning, and pruning
- Water at the base with drip irrigation rather than overhead, and keep foliage dry
Flower spikes showing up as the plant weakens
Since you are growing coleus for its leaves, those slim spikes of small blue-violet flowers are actually a problem, not a bonus. Once a plant flowers and sets seed in late summer, the whole foliage display falls apart and the plant loses its vigor. So pinch the spikes off the second you see them, and keep pinching to send that energy right back into the leaves.
Fix:
- Pinch or cut off flower spikes as soon as they appear
- Continue pinching to redirect energy into foliage
Wilting, drooping leaves
Coleus wilts fast when the soil dries out, and a potted one droops soonest of all, so check the soil before you worry. A thirsty plant usually bounces back within hours of a good drink, which is reassuring. A shade-loving type can also flag in too much afternoon sun, so if the soil is fine, just move it somewhere with a break from the heat.
Fix:
- Water thoroughly and keep soil lightly moist
- Increase watering frequency for containers
- Provide afternoon shade for non-sun-tolerant cultivars
Sticky leaves, warped growth, and bugs you can see
Indoor coleus draws sap-feeders, so you might spot soft white cottony mealybugs, clusters of aphids, or clouds of tiny whiteflies. In warm, dry rooms, spider mites can join in too, adding fine webbing and stippled leaves. Just rinse the plant off, keep it away from the others, and treat it with insecticidal soap, repeating until the bugs are gone for good.
Fix:
- Treat with insecticidal soap
- Rinse plants and isolate affected specimens
- Repeat treatments as needed for indoor infestations
Stretched-out stems going bare and pale
When the stems stretch out and the color fades, that is legginess, and it usually means the light is wrong for your cultivar or the tips never got pinched. A shade type bleaches in harsh sun, while a sun type stretches and pales in deep shade, leaving long gaps between leaves and bare lower stems. So move it to the right light, pinch the growing tips often, and cut the gangly stems back hard to push it into dense, full regrowth.
Fix:
- Move to the light level recommended for the cultivar (bright indirect light indoors; correct sun/shade outdoors)
- Pinch growing tips regularly to force branching
- Cut back leggy stems to encourage dense regrowth
Leaves bleached or scorched by strong sun
Most of the older coleus are shade-preferring, so when hot direct sun washes the color out of the leaves and starts wilting them, that is your sign. The simple fix is to move that plant to part shade or dappled light. Got your heart set on a bright, sunny spot? Then grab a sun-tolerant cultivar like Wasabi or Pineapple instead, since those hold their color in full sun.
Fix:
- Move shade-type cultivars to part shade or dappled light
- Choose sun-tolerant cultivars (e.g., 'Wasabi', 'Pineapple') for full-sun sites
Toxicity
Coleus is mildly toxic to pets, so it is worth a heads-up. The essential oils in the leaves can give cats and dogs vomiting, diarrhea, and skin irritation, and the ASPCA flags it as toxic to horses too. People are basically fine, though the sap can irritate skin, so just keep it away from pets and wash your hands once you are done pruning.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds · People
Cats Mild
The essential oils in the leaves are mildly toxic to cats. A cat that chews them usually drools and gets an upset stomach with some vomiting or diarrhea, and the sap can leave a bit of mouth or skin irritation.
Dogs Mild
A dog that nibbles the foliage tends to vomit, run loose stools, and skip its food for a day. It is a mild reaction, though the sap can also redden the skin and mouth.
Horses Mild
It lands on the ASPCA's toxic list for horses as well, since those same oils upset the gut and leave them dull and unwilling to eat. Best to keep any grazers well clear of the beds.
Rabbits Caution
Those aromatic oils that bother cats and dogs make coleus a poor pick around rabbits, so keep it out of reach rather than risk an upset gut.
Livestock Caution
Cattle, goats, and sheep are not well documented with coleus, but the same irritant oils call for caution, so fence it off from anything that grazes.
Birds Caution
There is not much hard data on birds, and pet species can be sensitive to plant oils, so just treat coleus as off-limits and keep it away from cages and aviaries.
People Caution
Coleus is basically safe for people, though the sap can irritate the skin. Handle it a lot and you might end up with an allergic rash, so wear gloves and wash up after pruning.
Wear gloves or wash hands after handling or pruning; repeated, frequent skin contact can cause allergic dermatitis
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
There are hundreds of coleus out there, but do not let that throw you, because they really come down to two groups: the shade-preferring ones and the newer sun-tolerant ones. These are the names you will bump into most.
'Wizard' series
A popular seed-grown series of compact, shade-preferring coleus that is easy to track down and quick to fill out.
'Kong' series
A shade lover grown for its huge leaves, which run way larger than those of most other coleus.
'Wasabi'
A sun-tolerant pick with bright chartreuse-green foliage that keeps its color even in a full-sun spot.
'Pineapple'
A sun-tolerant selection from the Pineapple group that you can count on where the light is strong.
'Alabama Sunset'
A sun-tolerant cultivar that handles bright light without bleaching the way the older shade types do.
How to propagate
Want more coleus? You are in luck, because it is about as easy as plants get, whether you root a spare cutting in a glass of water or start a tray from seed.
Stem cuttingsEasy
Spring through summer · Roots in about 2 weeks (often in water)
Coleus roots so willingly that a tip cutting dropped into a plain glass of water strikes roots in about two weeks. You can take cuttings any time from spring through summer. It is honestly the simplest way to carry a favorite through winter, since the parent will not make it through frost outdoors.
SeedEasy
Spring · Germinates in 10-15 days at 70-75°F
A lot of the named series get grown from seed. Sow in spring and keep the tray warm, around 70°F to 75°F (21°C to 24°C), and the seedlings come up in 10 to 15 days. Cuttings give you an exact copy of a plant, but seed is the easy way to fill a whole tray at once.
Myths
Coleus is grown for its flowers.
Coleus really earns its keep with those bold, multicolored leaves, not the flowers. The little blue-violet blooms are slight, and once they show up the plant tends to coast and lose vigor. Pinch the spikes off and the foliage stays at its best.
Coleus is harmless to pets.
The ASPCA lists coleus as toxic to cats, dogs, and horses thanks to the essential oils in its leaves. A pet that chews it can drool, vomit, and run loose stools, and the sap might irritate skin too. It is a mild reaction, but keep it out of reach all the same.
All coleus must be grown in shade.
The older cultivars really do prefer part shade and bleach in hot sun, which is where this whole idea comes from. But loads of newer selections are bred to hold their color out in full sun. What light it needs depends entirely on the cultivar you have got.