(Lamium amplexicaule subsp. amplexicaule)
Synonyms of Lamium amplexicaule (4) (Updated on 3-10-21): Galeobdolon amplexicaule (L.) Moench, Lamiella amplexicaulis (L.) E.Fourn., Lamiopsis amplexicaulis (L.) Opiz, Pollichia amplexicaulis (L.) Willd.
Synonyms of Lamium amplexicaule subsp. amplexicaule (7): Lamium amplexicaule f. albiflorum D.M.Moore, Lamium amplexicaule f. albiflorum Y.N.Lee, Lamium amplexicaule var. album Pickens & Pickens, Lamium amplexicaule var. clandestinum Rchb., Lamium mesogaeon Heldr. ex Boiss., Lamium rumelicum Velen., Lamium stepposum Kossko ex Klokov
Lamium amplexicaule L. is the correct and accepted scientific name for Henbit. The genus and species were named and described as such by Carl von Linnaeus in the second volume of the first edition of Species Plantarum in 1753.
Accepted infraspecific names: Lamium amplexicaule var. aleppicum (Boiss. & Hausskn.) Bornm., Lamium amplexicaule subsp. amplexicaule, Lamium amplexicaule var. bornmuelleri Mennema, Lamium amplexicaule var. incisum Boiss., Lamium amplexicaule subsp. mauritanicum (Gand. ex Batt.) Maire, Lamium amplexicaule var. orientale (Pacz.) Mennema. Lamium amplexicaule subsp. amplexicaule is the “type-specimen”. When infraspecific taxon are named, a “type-specimen” is automatically generated (autonym) whose description is closest to the (original) species. I am not sure how the species and type-specimen can have different synonyms…
Plants of the World Online lists 29 accepted species in the Lamium genus (as of 2-3-21 when I last updated this page). The genus is a member of the plant family Lamiaceae with 236 accepted genera. Those numbers could change as updates are made.
The above distribution map of Lamium amplexicaule is from Plants of the World Online. Areas in green are where the species is native and purple where it has been introduced. The USDA Plants Database map for Noth America is similar.
THERE ARE SEVERAL LINKS AT THE BOTTOM OF THE PAGE FOR FURTHER READING AND TO HELP WITH A BETTER POSITIVE ID.
Lamium amplexicaule is considered a winter annual that may begin flowering as early as February (depending on the winter). They have shallow taproots so they kind of fizzle out during the heat of the summer and go dormant. They return in the fall and might flower again.
I think the above photo, taken on February 21 (2020) is of young plants of Lamium amplexicaule. At this stage, they are very similar to Lamium purpureum (Deadnettle) but are easily distinguishable when they begin to flower. Glechoma hederaceum (Ground Ivy) also has very similar leaves but they don’t change. All three species grow together in the same areas and like the same conditions.
The above photo was taken on March 3 as some of the Henbit are beginning to flower. They are usually the second wildflowers to start blooming. The first was Veronica persicaria.
The leaves grow opposite one another on the stems. Lower leaves have long petioles (stems) while the upper leaves are sessile (without a petiole) and wrap around the stem. The upper leaves appear sort of frilly.
Lamium amplexicaule is sort of a sprawling plant that branches out at the base. I am not sure how long the stems could get since they are growing in the yard where I mow. Information online says they can grow up to 2 feet long. Lower portions of the stem are a reddish color but fade toward the top on some plants. The stems are 4-angled, hollow, and somewhat hairy (although they look smooth to me). They can also root from their leaf nodes.
This photo shows the leaves at the upper portion of the plant. They lack petioles (sessile) and wrap around the stems. The blue flowers in the photo are from Veronica persica (Bird’s Eye Speedwell)… Actually, they could be Wayside Speedwell (Veronica polita), I just haven’t figured it out quite yet. I kind of like the name Bird’s Eye better than Wayside…
Flowers are kind of tubular and have no petioles (sessile). They are produced at the top of the stem where the sessile leaves occur.
The stems produce 6-12 flowers that are approximately 1/2” long that are semi-erect. The upper lip is shaped like a hood while the lower lip is divided into two rounded lobes. Although their flowers are pollinated by insects, they occasionally produce cleistogamous (self-pollinating) flowers as well.
The outer surface of the corolla is a pinkish to purplish-pink color and the inner surface is white with purplish dots. The calyx is green, hairy, and has five teeth which I would love to get photos of… So far I have not been able to do that even using a magnifying glass. Practice makes perfect. 🙂
Even though today was rainy, I went outside to take a few photos of the Lamium purpureum that had started to flower. While I was at it I took a photo of the two Lamium species for a comparison photo. The tubes of the flowers of Lamium amplexicaule are much longer (at this point anyway) and the flowers are darker, especially the hood.
Lamium amplexicaule can be somewhat of a problem for some. They can invade yards and create bare spots when they go dormant allowing other weeds to grow. They could also be a problem in flower beds and gardens but being shallow-rooted they are easy to pull up.
Lamium amplexicaule are easy to distinguish from Lamium purpureum (Dead Nettle) because of their sessile orbicular leaves that war around the stems. Lamium purpureum does not have sessile leaves and grows in kind of a pagoda shape during flowering. Glechoma hederacea (Ground Ivy), also similar, flower later, have wider flowers, and all their leaves have petioles.
I will continue adding more photos because these are interesting plants
I have enjoyed photographing and learning about the many wildflowers growing on the farm and other areas. I have grown over 500 different plants and most have pages listed on the right side of the blog. I am not an expert, botanist, or horticulturalist. I just like growing, photographing and writing about my experience. I rely on several websites for ID and a horticulturalist I contact if I cannot figure them out. Wildflowers can be somewhat variable from location to location, so sometimes it gets a bit confusing. If you see I have made an error, please let me know so I can correct what I have written.
I hope you found this page useful and be sure to check the links below for more information. They were written by experts and provide much more information. If you can, I would appreciate it if you would click on the “Like” below and leave a comment. It helps us bloggers stay motivated. You can also send an email to me at email@example.com. I would enjoy hearing from you.
FOR FURTHER READING:
PLANTS OF THE WORLD ONLINE (GENUS/SPECIES)
WORLD FLORA ONLINE (GENUS/SPECIES)
MSU-MIDWEST WEEDS AND WILDFLOWERS
USDA PLANTS DATABASE
UNIVERSITY OF WISCONSIN
KANSAS WILDFLOWERS AND GRASSES
PFAF (PLANTS FOR A FUTURE)
EDIBLE WILD FOOD
NOTE: The figures may not match on these websites. It depends on when they make updates and when their sources make updates. Accepted scientific names change periodically and it can be hard to keep with. We are all a work in progress. 🙂