If I told you to let deadnettle liven up your mixed containers you might think that it is an oxymoron or perhaps I was just a moron, as dead and nettle sound none too lovely in the landscape. As they say in France, au contraire, deadnettle is the common name for a terrific perennial or annual if you choose by the name of Lamium.
Botanically speaking the plant is known as Lamium maculatum and is native to southern Europe and northern Africa. It is cold hardy from zones 4 through 8 meaning a large area of the country can enjoy it in some sort or fashion. (Much of southern Idaho is in zones 6-7.) There are now close to 30 varieties being sold in the United States. I regularly see Orchid Frost, Beacon Silver, Pink Chablis, a white flowered version called White Nancy and one with chartreuse margins called Anne Greenaway. Pink Chablis won awards in trials at the Dallas Arboretum, University of Georgia and J. C. Raulston Arboretum in North Carolina.
I’ve always loved it for the texture provided by its variegated foliage that looks silver and green then considered the lavender pink blooms that developed an added bonus. I find that this plant is often misunderstood or underappreciated by gardeners to say the least. If gardeners consider its Mediterranean climate-like heritage it really helps. By that I mean fertile soil and explicit drainage.
This stands to reason as the most riveting places I’ve watched them grow are in mixed containers with light fluffy soil that drains freely. In the landscape I’ve seen the captivating combinations with perennial salvias and shadier locations with ferns, hostas, ajuga and Chinese foxglove that all likewise require good internal drainage.
The Lamium maculatum varieties may be evergreen, semi-evergreen and deciduous depending on how mild your climate is. Your Internet search will show whatever you are hoping for with regard to the amount of sunlight they can take. My recommendation is morning sun and afternoon shade, or filtered shade. Never underestimate the ability of the silver foliage to add interest or brighten a shady location.
However the cooler the climate, the more sun they can take, hence I love them as a component plant in cool season mixed containers with pansies, snapdragons, dianthus, and other foliage. Lamiums offer an 8- to 12-inch tall plant with a spreading habit up to 24-inches, which is just perfect as a spiller plant.
Lamiums have some other terrific attributes. They are self-cleaning, which means no crawling into a big bed of groundcover to deadhead old flowers. About the only maintenance you'll be doing is a shearing back in early spring before growth resumes. One of the most loved traits however is that they are resistant to rabbits and deer.