Purple Deadnettle
Broadleaf weed
Purple deadnettle (Lamium purpureum) is a low-growing winter annual in the mint family that carpets lawns, gardens, and field edges in early spring. Gardeners and growers notice it because it greens up and blooms very early, often before most other plants break dormancy, forming soft purple-tinged patches that stand out in bare or thin ground.
How to identify it
Look for a square, four-sided stem typical of mint-family plants, usually growing 4 to 12 inches tall. The upper leaves are triangular to heart-shaped, softly hairy, and crowd toward the top of the stem where they take on a distinct reddish-purple tint, while lower leaves stay greener and have short stalks. Small pinkish-purple tube-shaped flowers appear tucked among the upper leaves in early spring. The plant has a shallow, fibrous root system and pulls up easily.
Where it grows
Purple deadnettle thrives in disturbed, moist, fertile soil and shows up in lawns, vegetable and flower gardens, cultivated fields, orchards, and roadsides. As a winter annual it germinates in fall, overwinters as a small rosette, then grows fast and flowers from late winter into spring before dying back as heat arrives. It spreads only by seed, and a single plant can produce large numbers of seeds that build up a reserve in the soil.
Why it is a problem
In gardens and crop fields it competes with young plants and seedlings for space, moisture, and soil nutrients, and dense early-season stands can slow the warming and drying of bare soil. Because it flowers so early, it can serve as a green bridge that hosts certain plant pests and diseases before crops emerge. It is not toxic and is generally considered a nuisance weed rather than a health hazard.
How to manage it
Hand pulling and shallow hoeing work well thanks to the shallow roots, and removing plants before they flower and set seed is the single most effective step for shrinking the problem over time. A layer of mulch in garden beds blocks light and suppresses fall germination, while keeping lawns thick and vigorous through proper mowing height, fertility, and overseeding leaves little bare ground for seedlings to establish. Because it is a winter annual, focus effort in fall and again in very early spring, and disturb soil as little as possible so you are not bringing more buried seed to the surface. Cleaning tools and boots between areas helps keep seed from spreading to new ground.
Commonly confused with
It is most often confused with henbit (Lamium amplexiflorum, commonly Lamium amplexicaule), another early-spring mint-family weed, but henbit has rounded, scalloped upper leaves that clasp the stem directly with no stalk, whereas purple deadnettle has stalked, triangular, purple-tinged upper leaves. It can also be mistaken for young ground ivy (creeping Charlie), which spreads by creeping stems rather than growing upright from seed.
General guidance for US lawns and gardens, focused on prevention and non-chemical control. For a confirmed identification and options specific to your area, contact your local Cooperative Extension office. Page updated Aug 4, 2026.