Fields covered with large swaths of lavender-tinted flowers are a common sight in rural Missouri this time of year. Pretty weeds, that’s all they are. Just henbit. You probably have a few here and there in your yard. They’re not particularly noticible in small numbers.
Henbit (Lamium amplexicaule) is a winter [...]

A different view, showing the leaves. Henbit blooms in late winter and early spring. It started in late January here at the farm and didn’t seem too bothered by freezing weather.