Henbit (Lamium amplexicaule L.) is a cool-season annual weed common throughout Louisiana. As a member of the mint family, it can be distinguished by its four-sided, square-shaped stem. Henbit produces flowers in the spring and spreads through seed. It can be found growing in areas with thin turfgrass and can tolerate some shade as well. This weed is commonly confused with purple deadnettle (Lamium purpureum).
Henbit
Henbit has medium green leaves, which are oppositely arranged along the stem. Leaves are circular to heart-shaped with round-toothed edges with hairs on the upper leaf surface and on the veins of the lower surface. Stems are green to purple in color and are four-sided (square). Both leaves and stems can be sparsely hairy. Flowers are purple and tubular. They grow near leaf axils or where leaves are attached to the stem. Henbit freely branches from the base and can have both an upright and prostrate growth habit. For more information on henbit identification and characterization, visit the USDA Plants Database at https://plants.usda.gov.
Leaves with lobed edges
Purple tubular flower
Square stem
Growth habit
The best way to prevent or reduce weed encroachment is to maintain a healthy lawn through proper fertilization and soil pH management and regular mowing. Properly maintaining a lawn through these cultural practices promotes dense and vigorous turfgrass, allowing it to better compete with weeds. Below are the recommended mowing heights and nitrogen fertility rates recommended for each turfgrass species. In addition to these lawn care practices, manual removal of weeds may also be necessary.
Turfgrass | Mowing Height | Nitrogen Rate (per 1000 ft2 per year) |
---|---|---|
Bermudagrass | 1 - 2 inches | Up to 3 pounds |
Centipedegrass | 1 - 2.5 inches | Up to 2 pounds |
St. Augustinegrass | 2.5 - 3 inches | Up to 3 pounds |
Zoysiagrass | 1 - 2.5 inches | Up 2 pounds |
In addition to cultural practices, herbicide applications may be required to achieve effective weed control. Henbit is readily controlled by several pre-emergence and post-emergence herbicides.
When applying any type of herbicide, you must follow the manufacturer’s labeled directions.
For more information regarding pesticides for turfgrass, please reference the Louisiana Suggested Chemical Weed Control Guide at the LSU AgCenter website, www.lsuagcenter.com.
St. Augustinegrass | Centipedegrass | Zoysia | Bermudagrass | |
---|---|---|---|---|
Pre-emergence Herbicide Active Ingredients | ||||
atrazine | x | x | x | dormant |
simazine | x | x | x | x |
isoxaben | x | x | x | x |
oryzalin | x | x | x | x |
dithiopyr | x | x | x | x |
prodiamine | x | x | x | x |
pendimethalin | x | x | x | x |
Post-emergence Herbicide Active Ingredients | ||||
atrazine | x | x | x | dormant |
simazine | x | x | x | x |
2,4-D + dicamba + mecoprop | x | x | x | x |
2,4-D + dicamba + mecoprop + carfentrazone | x | x | x | x |
thiencarbazone + iodosulfuron + dicamba | x | x | x | x |
penoxulam + sulfentrazone + dicamba + 2,4-D | x | x | x | x |
metsulfuron | x | x | x | x |
metsulfuron + dicamba | x | x | x | x |
metsulfuron + sulfentrazone | x | x | x | x |
For information regarding weed identification and control options please contact your local LSU AgCenter Extension Parish Office. To find your local LSU AgCenter Extension Parish Office visit www.lsuagcenter.com.