Henbit (Lamium amplexicaule) is a winter annual weed that can be found throughout the United States. Unfortunately, this weed can start producing small purple flowers come springtime that result in an abundance of seeds (up to 2,000 per plant). Henbit seeds will germinate during the fall and through the winter; however, plants may remain relatively small and dormant until the early spring when the plants grow rapidly and the problem in your lawn becomes noticeable.
These weeds can be identified by their square stems that are green to purple in color, their heart-shaped leaves that grow in pairs with scalloped edges and their unique reddish-purple flowers. This weed can be confused with purple deadnettle; however, purple deadnettle produces triangular leaves that have a distinct reddish-purple color, which helps to tell these plants apart. Read below to find out how to get rid of henbit with both cultural, non-chemical methods as well as with a few effective products.
Henbit Non-Chemical Control
When it comes to controlling henbit, there are a few cultural controls you can implement before moving to chemical options. This weed has a fibrous root system and if you can identify it while the problem is small and before the plant has produced seed, this weed can be pulled by hand. This can be done by digging around the plant to help loosen the soil, or by making the soil moist to allow it to be easily tugged out.
Henbit does well in a variety of conditions, but seems to thrive in areas of the lawn that are thin, overly moist or shady. Therefore, maintaining a thick lawn with no thin, weak areas can prevent henbit from developing and taking over. This can be done by properly irrigating, mowing on a correct schedule and at the proper height for your grass type and having a fertilization program that provides the nutrients necessary to keep your grass healthy. Here are some of our favorite fertilizer selections:
Henbit Chemical Control
Complete control of henbit is easier in the fall if you are able to identify the plants while they are still young and small or if you are able to put out a pre-emergent herbicide before seeds germinate. The difference between a pre-emergent and post-emergent herbicide is that a pre-emergent herbicide should be applied before a weed grows while a post-emergent herbicide should be applied if you already have weeds in your lawn. Pre-emergents are typically applied in the spring and in the fall.
One option for this can be found with the pre-emergent Dimension by Dow AgroSciences (active ingredient: Dithiopyr). This product is mixed into a spray tank for easy application across a specific area or an entire lawn and can provide season long control of weeds. A few other effective pre-emergents for henbit include Tenacity, which is a pre- and post-emergent, Prodiamine 65 WDG and Crabgrass Control Plus 0-0-7 with 0.37% Prodiamine. When applied at the correct time, in the early fall before henbit seeds begin to germinate, these products can be very effective at preventing a henbit infestation.
If henbit is already present in your lawn, there are also post-emergent options for control. One post-emergent can be found with Spectracide Weed Stop (active ingredients: 2,4-D, Mecoprop-p, Dicamba, and Sulfentrazone) or Spectracide Weed Stop for St. Augustine and Centipede Lawns. These product connects directly to your hose, making it easy to spray. Check out some of the best henbit weed killers below.
Ideally, control of henbit will happen before the plants begin to flower and produce seed. If this is not possible, the total control of this weed may take multiple seasons and a variety of efforts including both cultural and chemical controls. If chemical controls are necessary, the labels on the herbicides must be followed carefully so that the product does not damage your lawn or cause you any harm. Improper use of herbicides is dangerous for both you and your lawn.