You can overwinter ajuga with very little effort in most areas. This plant is hardy in USDA zones 3-10, so it handles cold on its own. Your main job is to help it through the toughest months and clean up damage in spring.
I've grown ajuga through winters in zone 5 for over ten years now. The plants flatten down once hard frost hits but rarely die back all the way. Some years the leaves look rough by March, while other years they stay green through snow cover. Spring cleanup takes me about fifteen minutes for a large bed.
Ajuga keeps its foliage through winter because the roots stay alive below the frost line. The leaves may bronze or darken as temperatures drop, but they don't fall off like deciduous plants. This semi-evergreen habit gives you year-round coverage even when the plant goes dormant above ground.
Your ajuga winter care tasks stay simple no matter where you garden. Stop fertilizing by late summer so the plant can harden off before frost. Keep watering until the ground freezes since dry roots suffer more cold damage. Don't cut back the foliage since those leaves protect the crown.
Protecting bugleweed in winter matters most in zones 3-5 where deep freezes occur. Add 1 inch of mulch after the first hard frost to protect roots from heaving. Use pine straw or shredded leaves that won't pack down and smother the crowns. Pull this mulch back in early spring when snow melts.
In my experience, the biggest winter problem is freeze-thaw cycling rather than cold itself. Plants get pushed out of the ground when soil freezes and thaws over and over. You'll see exposed roots and tilted rosettes after a rough winter. Press these plants back into the soil in early spring.
Know the difference between normal winter damage and crown rot. Winter damage shows brown leaf edges and flattened rosettes that perk up once warmth returns. Crown rot creates mushy centers and spreads through the planting. Damaged plants recover; rotted plants need removal.
Spring cleanup goes fast if you let it. Run your fingers through the bed to pull out any brown or dead leaves. Leave anything that still feels green and pliable. Fresh rosettes will hide last year's damage within a few weeks of warm weather. New growth fills in fast once soil warms.
Container-grown ajuga needs more winter protection than plants in the ground. Move pots to a sheltered spot against your house foundation. Wrap the container in burlap or bubble wrap to keep roots from freezing solid. Check soil moisture monthly since containers dry out even in winter.
Read the full article: Ajuga Ground Cover: Complete Growing Guide
