Download Pretty Purple Weeds One of the most common flowers in my lawn is

Pretty Purple Weeds
One of the most common flowers in my lawn is ground ivy, also known as gill-over ground, creeping Charlie,
creeping Jenny, field balm, and several other names. Botanically it is called Glecohoma hederacea. It has pretty
purplish-blue flowers that are bilaterally symmetrical. The leaves are small, generally less than an inch wide
scalloped along the edges, and hairy. As a member of the mint family, gill-over-ground has a square stem that
creeps along the ground with the plants never getting more than 8 inches tall. If you crush the plant or mow it, it
releases a minty aroma. It grows in grassy lawns and does particularly well on top of mulch beds and around the
base of trees and shrubs where the conditions tend to be shady and moist.
As is the case for many of our abundant plant, ground ivy originated in Europa and southern Asia. It was probably
brought to North America in the late 1600’s intentionally for use as an herbal remedy. Today it has spread
throughout the US and has found everywhere outside of the desert southwest.
There are several other plants that are considered either weed or ornamental plants, that could be confused with
ground ivy. Common mallow (Malva neglecta) has round, scalloped leaves, but the leaves are larger, the stem is
round instead of square, and the flowers of mallow have five petals extending out radially. Two Lamium species,
henbit (L. amplexicaule) and purple dead nettle (L. purpureum) are also mint and have a square stem. However,
their flowers are more reddish to purple, the leaves are larger, and the stems are more erect than creeping.
Historically, beer makers used ground ivy in addition to or as a substitute for hops in brewing beer, particularly in
Britain. Old English recipes sometimes included ground ivy as in ingredient in oatmeal, vegetable dishes, jams, and
soups. Many herbalists suggest that ground ivy can be used for teas and tinctures and it has been credited with a
variety of healing properties. In modern herbal medicine suggests using ground ivy as an astringent, a diuretic, and
a stimulant. In contrast, the plant can be toxic to cattle and other ruminants. It can also be toxic to horses if it is in
large enough quantities in the field or in their hay. On the other hand, some species of invertebrates and wild
mammals apparently eat it without ill effect. Wild boars in the southeastern US have been observed eating ground
ivy. However, in spite of its inclusion in many lists of edible or medicinal plants, its safety for human consumption
has not been rigorously tested.
Ground ivy has an unusual way of reproducing. It has two different flower types. On type is female only and the
other type possesses both female and male floral parts. The female flower cannot self-pollinate but scientists are
not sure if the flower containing both male and female parts can self-pollinate. Each flower produces four seeds
which are dispersed either by ants or simply by falling to the ground. The seeds live only one or two years in the
soil.
Even though many people believe that ground ivy is a weed, there are cultivated varieties in the horticultural
trade. Most of these varieties have variegated leaves. As is usually the case the distinction between a wildflower
and a weed is in the eye of the beholder. Take a look in your lawn or in places that damp and see if you can find
some ground ivy this spring.
PHOTO: Ground ivy in a lawn in Alliance Ohio in late April. Note the bluish bilateral flowers. The scalloped leaves
and the square stem that collectively distinguish this plant. (By CM 4/24/2016)