Henbit (Lamium amplexicaule) and Chickweed (Stellaria media and Cerastium fontanum) are common weeds that appear in lawns and gardens, particularly from late winter to early spring. These cool-season annuals thrive in cooler temperatures when turfgrass is often dormant, allowing them to establish a strong foothold. Their dense growth and prolific seed production confirm the difficulty of their elimination. Successfully controlling these weeds requires a strategy that addresses both immediate removal and long-term prevention.
Understanding Henbit and Chickweed
These two weeds are frequently seen together because they share the same life cycle as winter annuals. Seeds typically germinate in the late summer or fall when soil temperatures drop, and the small seedlings survive the winter. As temperatures rise in early spring, these plants grow rapidly, flower, and produce new seeds before dying off naturally with the onset of summer heat.
Accurate identification helps select the most effective removal method. Henbit is characterized by its distinct square stem and small, reddish-purple, trumpet-shaped flowers that appear in whorls near the top of the plant. Its upper leaves lack stalks, appearing to clasp the stem directly. Chickweed forms dense, low-growing mats with thin, round stems and small, bright green, egg-shaped leaves. Its tiny white flowers have five petals that are so deeply notched they appear to be ten separate petals. The primary goal of control is to disrupt this annual cycle by preventing spring seed drop.
Non-Chemical Removal Methods
For those who prefer to avoid chemical treatments, physical removal is a highly effective option, especially when the infestation is small or manageable. Manual removal, or hand-pulling, works best when the weeds are young and the soil is moist, which helps ensure the entire root system is extracted. Common chickweed is shallow-rooted, making it relatively easy to pull up, but it is important to remove the entire sprawling mat to prevent re-sprouting from rooted stem nodes.
Henbit has a fibrous root system and is easily removed by hand when small. Mowing can serve as a cultural control for henbit; setting the mower low clips off flower heads and prevents the plant from developing and dispersing its seeds. However, the low-growing, creeping nature of chickweed means that regular mowing is ineffective at preventing its seed production.
Another non-chemical approach involves using cultural practices to make the environment less hospitable. Henbit and chickweed thrive in thin, weak, or patchy areas of the lawn where they face little competition for sunlight and nutrients. Applying a thick layer of organic mulch, such as wood chips or straw, in garden beds or around trees will smother emerging seedlings by blocking light. In bare-soil areas, solarization—covering the area with clear plastic sheeting to heat the soil and kill seeds—can be used before planting.
Selecting and Applying Herbicides
Chemical control is often the most practical solution for widespread infestations, requiring a dual strategy involving both pre-emergent and post-emergent products. Post-emergent herbicides are designed to kill weeds that are already visible and actively growing. For these broadleaf weeds, selective herbicides containing active ingredients like 2,4-D, dicamba, and MCPP (often sold as a three-way combination) are recommended.
These herbicides are effective when applied to young, actively growing weeds during periods of moderate temperatures, ideally above 50 degrees Fahrenheit. Applying them too late in the spring, when the weeds are mature and beginning to die off naturally, is less effective and may be a waste of product. Always read the product label carefully to ensure the herbicide is safe for your specific grass type and follow all instructions regarding application rates and local regulations.
Pre-emergent herbicides are the preventative chemical strategy, acting as a barrier to stop weed seeds from germinating. This is the most successful method for breaking the life cycle of winter annuals. Products containing ingredients such as prodiamine or pendimethalin should be applied in the fall, typically between late August and mid-September, before the henbit and chickweed seeds begin to sprout. This timing is critical because the product must be in place before germination to prevent emergence the following spring.
Long-Term Prevention Strategies
A successful long-term strategy focuses on improving the overall health and density of the turf to prevent future weed invasion. A thick, healthy lawn naturally crowds out emerging weed seedlings by monopolizing available sunlight, water, and soil nutrients. This is achieved through consistent fertilization throughout the growing season to encourage robust turf growth.
Proper mowing height is equally important, as taller grass blades promote deeper root growth and help shade the soil, which inhibits weed seed germination. For cool-season turf, maintaining a height between 2.5 and 3.5 inches is recommended. Overseeding thin areas of the lawn in the fall with desirable grass varieties increases turf density, reducing the bare patches where henbit and chickweed establish themselves.
The cornerstone of prevention remains the strategic timing of cultural and chemical controls. Reapplying a pre-emergent herbicide every fall is the most reliable way to prevent the emergence of new winter annuals in the spring. By consistently prioritizing soil health, turf density, and timed preventative measures, the cycle of these weeds can be broken over multiple seasons.