I’m going to take a break from weeding my garden to recognize two very fast-spreading members of the mint family (Laminaceae). The first one gets the Award for being “Most Insufferable”.
Gill-over-the-ground (AKA Ground Ivy or Creeping Charlie) is a low-growing mint with a creeping habit. Like many garden weeds, it tolerates the erratic temperature changes of early spring (it doesn’t mind the cold) and therefore get’s a head start on many of its springtime competitors. It grows quickly and puts out flowers long before most plants even emerge from the ground. This aggressive growth tactic makes it both extremely successful and impossibly annoying.
Because gill-over-the-ground can be confused with another cool-season mint, purple dead nettle, I’ll address both as well as how you can tell them apart.
Gill-over-the-ground: the leaf shape of this plant is round or reniform (kidney-shaped). The leaf margins are strongly scalloped. The veins are palmate. The leaves are opposite, hairy, and aromatic when crushed. Each leaf has a petiole (or stem). The blue to lavender flowers flowers grow in clusters near the top of the stem. The flowers are funnel shaped, bilaterally symmetrical, and have lower and upper lips.
Purple dead nettle (Lamium purpureum): unlike the previous “creeping” plant, this one grows upright (4-16 inches in height). The leaves are opposite and overlapped in such a way that the plant resembles a small pogoda. The slightly hairy leaves are heart-shaped (with pointed tips) and have wavy edges. They have petioles. The leaf color varies from green at the bottom of the plant to purplish near the top of the plant (hence the name purple dead nettle).
The flowers of purple dead nettle are similar to gill-over-the-ground: they are funnel-shaped, pinkish purple, bilaterally symmetrical, with lower and upper lips. The lower lip is split into two lobes.
The “dead” part of the dead nettle name refers to the fact that the leaves do not cause stinging (the sting is dead) even though they resemble nettles.
Both gill-over-the-ground and purple dead nettle provide nectar and pollen for honey bees early in the season (when few other flowers are blooming). Both plants are edible in salads and have some medicinal uses. None of these fine qualities is a consolation to me though, because right now my garden is literally carpeted with these two mints. So if you’ll excuse me, I need to get back to my weeding!