Henbit (Lamium amplexicaule) is a widespread, low-growing plant often mistaken for other common broadleaf weeds. It is notable for its remarkably early appearance and flowering period, providing one of the first splashes of color in disturbed landscapes before many other plants have broken dormancy. Henbit thrives in cool weather and completes its life cycle rapidly, which allows it to bloom exceptionally early in the year.
Identifying Henbit
Identifying Henbit involves noting its distinct physical characteristics, which separate it from similar early-season plants. Its stems are four-sided, or square, a characteristic shared by plants in the mint family. The leaves are rounded or broadly egg-shaped, featuring scalloped or bluntly toothed margins.
A key identification feature is the difference between the upper and lower leaves. The lower leaves are attached to the stem by small stalks, but the upper leaves lack these stalks and appear to wrap around or clasp the stem. The flowers are small, tubular, and typically reddish-purple or purplish-pink. They emerge in whorls, or rings, located in the axils of the upper, clasping leaves.
The Timing and Duration of Blooms
Henbit’s flowering period is directly tied to warming temperatures following winter, often beginning in late winter or very early spring. Depending on the local climate, blooms can start as early as February in warmer regions and continue through May in cooler areas. It is frequently one of the first broadleaf species to flower, making it visible when lawns and garden beds are otherwise dormant.
The bloom is triggered by brief periods of warming, allowing the plant to take advantage of favorable temperatures for growth and reproduction. This early flowering strategy helps the plant set seed before the competitive summer heat arrives. The individual blooming period can last for a month or two, resulting in a continuous presence of color across an area.
Henbit tolerates light frost, meaning the plant often survives and continues its reproductive cycle even if a cold snap follows the initial warm period. This resilience allows it to maintain its vibrant pink-purple flowers through the unpredictable weather of early spring. Seed production is rapid, helping the plant complete its life cycle quickly once flowering begins.
Life Cycle and Growth Conditions
Henbit is classified as a winter annual, meaning its life cycle begins and ends within a cold-to-warm seasonal window. Seeds typically germinate in the cool temperatures of late summer or fall, or sometimes during mild periods in winter. The plant survives the cold season as a small, low-growing rosette of leaves close to the ground.
Once spring arrives and temperatures consistently rise, the plant rapidly bolts, producing its characteristic square stems and flowers. This quick growth allows it to flower and set seed before the intense heat of summer arrives. Henbit generally dies out completely as high summer temperatures take hold.
Henbit grows best in disturbed soils, thin turf, and areas where competition from more robust summer grasses is minimal. Preferred habitats include garden beds, lawns with sparse coverage, and recently tilled agricultural fields. The plant’s shallow, fibrous root system allows it to establish quickly in these bare or exposed areas.