Ajuga Plant Guide: How to Plant and Care for Ajuga

The plant genus ajuga (Ajuga reptans) encompasses plants also commonly referred to as carpetweed, bugleweed, bugle, blue bugle, bugleherb, carpet bugle, carpet bugleweed, and common bugle. These species are also members of the mint family Lamiaceae and are vigorous growers that can quickly fill a large area.

With normally blue or purple flowers—though they can be found in white—ajugas are deer-resistant and thrive in shady areas while also adding colorful green, purple, bronze, or black foliage to your landscape. Low to the ground, ajuga plants provide effective erosion control while also limiting the space where weeds might otherwise grow. As evergreen, herbaceous perennials, ajuga can easily grow out of control without the proper care despite typically only growing about 4–8 inches tall.

Ajuga plants are low-maintenance and highly versatile, and their diverse foliage colors make them perfect for planting under trees or shrubs, or on banks or slopes. Here are seven popular cultivars (plants created through selective breeding):

1. 1. ‘Black Scallop’ (A. reptans): This creeping perennial is known for its purple-black leaves with scalloped edges and its fragrant, deep blue flowers that bloom between late spring and early summer.
2. 2. ‘Blueberry Muffin’ (A. reptans): This evergreen perennial’s blue flowers and thick, weather-resistant leaves will quickly form a dense mat of rosettes. This plant can grow in USDA hardiness zones 5–9 and with regular watering can grow about 6 inches in height.
3. 3. ‘Bronze Beauty’ (A. reptans): Known for its bronze-tinged leaves and rich blue flowers, this variety is great for planting between stepping stones or in wall crevices since it quickly forms a dense mat of rosettes.
4. 4. ‘Burgundy Glow’ (A. reptans): A slower spreader compared to the growth of other varieties, ‘Burgundy Glow’ is known for its tricolor foliage—cream, rose-burgundy, and dark green leaves—as well as its blue flower spikes. During the fall, older leaves will take on a bronze hue while the younger leaves are rosier in color. This popular variety can grow to about 10 inches in height.
5. 5. ‘Catlin’s Giant’ (A. reptans): This variety is known for its 6-inch-long, glossy, purplish-bronze leaves and blue-violet rosettes arranged on spikes that can be 12 inches tall. This ajuga variety can also spread 1–2 feet across.
6. 6. ‘Chocolate Chip’ (A. reptans): Also known as ‘Valfredda,’ this is a dwarf variety of ajuga with chocolate-burgundy leaves and blue-purple flowers that are on display starting in spring. These are evergreen in most regions.
7. 7. ‘Purple Brocade’ (A. reptans): This variety does well in USDA hardiness zones 3–9 and has blue-violet flowers and deep green leaves with purple margins. Purple brocades are also known for being less aggressive growers than many other types of ajuga plants.

Ajugas should be planted in early spring in areas with rich soil that receive either full shade or partial shade (they grow best in partially shady areas). Plants should be spaced 8–15 inches apart. Caution should be used to avoid planting ajugas too deeply or covering the crown with soil to prevent the crown from rotting. After planting, immediately mulch your ajuga with a layer of shredded bark to keep weeds from smothering these young plants. The space between the plants should fill in within a year or two.

Ajuga is especially ideal for rounding out a pot with other plants because it fills in gaps well. Use a well-draining container and place the plant in an area with good air circulation. Ajuga can form colorful pairs with other perennials like yarrow, campanula, coreopsis, geraniums, or primroses. Since ajuga plants are partially resistant to dry conditions, you can consider companion plants like thrift, creeping thyme, sedum, or hens and chicks.

Ajuga plants require very little care—unless yours receives a lot of sunlight or becomes particularly dry. Here are six tips for caring for your ajuga plant:

1. 1. Growth control: Ajuga ground cover spreads through underground, stem-like growths, also called runners or stolons, that extend from a mother plant. Since ajuga plants are known for their quick growth and mat-forming traits, use only a few plants in strategic locations and stay on top of edging around your garden or other landscaping to keep these plants under control and within bounds. Ajugas should be thinned every three years or so to prevent overcrowding.
2. 2. Division: Ajuga runners can form clumps as they root the plant in soil. If these clumps become too crowded, causing the plant to lose its vigor, lift the runners and divide them. This can be done by digging out the clumps and either pulling them apart or cutting them into smaller sections to be replanted elsewhere.
3. 3. Light: Planting ajugas in sunnier areas can slow the growth of your plants, making it easier to keep their growth under control.
4. 4. Soil and water: Soil should be moist, though ajuga plants are adaptable and can even be drought-tolerant. These plants are able to sustain themselves on normal rainfall, though watering may be necessary for times where it is particularly dry or if your plant is located somewhere with full sun exposure. You don’t need to fertilize this plant.
5. 5. Propagation: While ajuga plants can quickly become invasive, their self-seeding nature also makes them easy to propagate. Runners can be cut and replanted elsewhere. If you’re propagating them from seeds, sow the seeds in containers during fall or spring, covering them with a thin layer of compost and keeping the soil moist. These seeds should germinate in a month or less. During the summer, you can move your young plants to your garden.
6. 6. Pruning: Deadheading—removing faded or dead flowers from the plant—can help with the overall appearance of ajuga plants. Should you want to adjust the ground cover, runners can be easily removed or redirected by simply lifting the runners and pointing them in the direction you’d like them to go.

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