Ornamental · Lamiaceae
Bugleweed
Ajuga reptans
Give it part shade and good drainage, and bugleweed lays down a fast carpet of color, so long as you keep it in bounds.
Partial shade
Every 5–10 days
USDA 3–9
4–9 in · 10–23 cm
Overview
Bugleweed is a low, fast groundcover from the mint family, grown for the dense mat of glossy leaves it spreads across shady ground. In mid to late spring it throws up short spikes of blue flowers that lift above the foliage. It shrugs off cold to USDA zone 3 and takes everything from full sun to deep shade, which is why it turns up under trees and on slopes where little else will hold.
What makes it useful is also what makes it a handful. It travels by stolons, above-ground runners that root as they go, and a single plant knits into a solid carpet within a season or two. Left unchecked it walks straight out of the bed and into the lawn, so the real work with bugleweed is less about keeping it alive and more about keeping it where you want it.
Set it in average, well-drained soil with room for air to move and it asks for almost nothing. The one weakness to respect is crown rot, which takes hold fast in heavy, wet ground or a crowded mat during a humid summer.
Care
The short version: part shade suits it best, though it handles sun to full shade, in average soil that drains well. Keep it evenly moist without letting the ground stay soggy, divide every couple of years, and edge the bed so it can't wander.
Light
Bugleweed does best in part shade, but it's far more flexible than most groundcovers. It will take everything from full sun to deep shade, though leaf color tends to run richest with a bit of shelter from the harshest afternoon light.
Water
Keep the soil evenly moist and let it dry a touch between waterings, roughly every 5 to 10 days once established. It will ride out a moderately dry spell, but standing wet is the real danger, since soggy ground invites crown rot.
Soil
Plant in average, humusy, well-drained loam. A pH from 5.5 to 7.0 suits it, and it copes with clay or sand, but it will not forgive soggy, poorly drained ground for long.
Temperature
This is a tough plant, hardy across a huge range from -40°F to 100°F (-40°C to 38°C). Cold is no obstacle. Heat paired with humidity is the bigger worry, since that combination is what wakes up crown rot.
Humidity
Ordinary outdoor humidity is fine, so there's no figure to aim for. Air movement is what counts, because muggy, still air over a crowded mat is exactly the setup that rot needs to spread.
Feeding
Bugleweed rarely needs feeding and usually does fine on its own in decent ground. If the planting looks tired, a light spring topdressing of compost or a balanced fertilizer is plenty.
Pruning
Shear or mow off the spent flower spikes after bloom to neaten the planting, and cut ragged foliage back hard to bring it around. Dividing every 2 to 3 years does double duty, relieving crowding and cutting the risk of crown rot.
Repotting
Rather than potting on, bugleweed gets lifted and divided every 2 to 3 years once it grows crowded. Watch for dense, matted growth, dead or thinning centers, and weaker flowering, all signs it's time to split.
Size & spacing
Plants stay low, just 4 to 9 inches (10 to 23 cm) tall, but each one spreads 12 to 24 inches (30 to 60 cm) wide and keeps going. Space with that spread in mind, since the runners will close any gaps you leave on their own.
When to plant
Bugleweed is a hardy perennial with no fussy planting window. Set new plants out in spring or fall while the weather is mild, and the blue flower spikes follow in mid to late spring, roughly May into June.
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: Mid to late spring (roughly May to June)
Hardiness
USDA hardiness zones: 3–9
Temperature: down to -40°C
Troubleshooting
Most bugleweed trouble falls into two camps: the plant spreading where it shouldn't, and rot setting in where the ground stays wet. Both are easier to head off than to fix. Match what you're seeing below and act while the planting is still healthy.
Round patches that wilt and die out overnight
This is crown and root rot, a fungal collapse that strikes in hot, humid weather and spreads in circles through a crowded mat. The crowns turn mushy right at the soil line, and a whole planting can go down with it. Dig out the dead patches along with the infested soil around them, then open the bed up with better drainage and thinning so air can move through.
Fix:
- Remove and discard affected plants and surrounding infested soil
- Improve drainage and increase air circulation by thinning
- Divide crowded plantings every 2-3 years
- Apply a labeled fungicide where the problem is severe
Bugleweed creeping into the lawn and nearby beds
This is the plant doing what it does best, sending out stolons that root wherever they touch down and turn up as new rosettes in the turf. Trace the runners back to the main patch and pull the strays, rooted plantlets and all. A deep edging between bed and lawn is the surest way to hold the line, and dividing every couple of years keeps the colony from pushing outward in the first place.
Fix:
- Pull or dig out runners and stray rosettes, removing rooted plantlets entirely
- Install a deep physical edging or hard border between the bed and lawn
- Divide and thin the planting regularly to keep it contained
- Avoid using it as a direct lawn edging
Weak, stunted plants that fade despite good care
When plants lose vigor for no obvious reason, suspect root-knot nematodes working below ground or aphids clustered on the new growth above it. Lift a struggling plant and check the roots for galls, then look over the tips for the insects. Hose aphids off or hit them with insecticidal soap, but pull out nematode-stricken plants and don't replant a susceptible groundcover in the same ground.
Fix:
- Remove severely affected plants and avoid replanting susceptible groundcover in the same spot
- Rinse aphids off with water or treat with insecticidal soap
- Maintain plant vigor with proper spacing and drainage
Toxicity
Good news for households with pets and kids. Bugleweed isn't on the toxic-plant lists, and it's treated as safe around cats, dogs, and people alike. The most a curious mouthful might bring is a brief stomach upset, the same as with many plants that aren't meant to be eaten.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats None
Bugleweed isn't toxic to cats, so a curious nibble is nothing to worry about. A cat that eats a big mouthful might get a brief upset stomach, the same way any non-food plant can disagree with them.
Dogs None
Dogs can chew the foliage without any real risk. The worst you'll likely see from a large helping is some passing drool or a loose stool that clears on its own.
Horses Safe
There's nothing in bugleweed that poisons horses, and it isn't known to cause them trouble. A horse that grazes a patch should be perfectly fine.
Rabbits Safe
Rabbits can browse the leaves safely, with no toxic compounds to worry about. As with any new green, introduce it slowly so their gut has time to adjust.
Livestock Safe
Cattle, goats, and sheep face no poisoning risk from grazing bugleweed. It simply isn't a plant that turns up on the toxic lists for farm animals.
Birds Safe
Backyard hens and other birds can peck at the foliage without harm. None of the parts hold anything dangerous to them.
People Safe
Bugleweed poses no poisoning hazard to people, including children who put a leaf in their mouth. It's grown for the carpet of color it lays down, not for eating, so there's no reason to make a meal of it.
Not poisonous, but pets that nibble the foliage may experience mild, temporary stomach upset, as with many non-food plants.
Varieties
Beyond the plain green species, bugleweed comes in a run of selections grown for leaf color, size, and habit. These are the ones worth knowing by name.
Burgundy Glow
Its tricolor leaves blend pink, cream, and green for a softer, brighter mat than the plain species.
Black Scallop ('Binblasca')
The glossy, scalloped leaves run so dark they read as near-black in the bed.
Catlin's Giant
Larger bronze-green leaves and unusually tall flower spikes give this one more presence than most.
Chocolate Chip ('Valfredda')
Small, narrow, glossy chocolate-burgundy leaves make this a smaller, more restrained pick for tight spots.
Ajuga genevensis (Geneva bugleweed)
This related species spreads without runners, so it stays far less invasive and takes more sun than common bugleweed.
How to propagate
Bugleweed is among the easiest plants to multiply, since it spends its whole life making copies of itself. Splitting a clump or lifting a rooted runner gives you new plants for nothing.
DivisionEasy
Spring or fall · A few weeks to one season
Division is the easiest and most common way to make more bugleweed. Lift a crowded clump in spring or fall, pull apart the rooted rosettes and runners, and replant them, and the divisions settle in within a few weeks to a season. Doing this every 2 to 3 years also keeps crown rot at bay.
LayeringEasy
Growing season · A few weeks
The plant layers itself for free. During the growing season, rooted plantlets form along the stolons on their own, and you just sever a well-rooted one and move it, where it takes hold in a few weeks.
SeedModerate
Spring · One season or more
You can raise the species from seed sown in spring, though it takes a season or more to fill in. Named cultivars are the catch, since they don't come true from seed and are better split by division.
Myths
Bugleweed is a tidy groundcover that stays neatly where you plant it.
It travels by above-ground stolons and escapes its bed with ease, rooting into lawns and neighboring plantings before you notice. Plan on firm containment from the start, and give it the drainage and air movement it needs to fend off crown rot.