Splitlip Hempnettle: Medicinal Uses & Care Tips

What Is Splitlip Hempnettle and Where Does It Come From?

Splitlip hempnettle is a fast-growing annual wildflower in the mint family (Lamiaceae), native across Europe and temperate Asia and now widely naturalized in Canada, the northern United States, and Alaska. It grows as an erect, bristly-haired herb up to about a meter tall, with square stems noticeably swollen below the leaf nodes and opposite, serrated, ovate leaves. From midsummer into autumn it produces small, two-lipped tubular flowers in shades of purple, pink, or white, clustered densely near the stem tips -- the notched lower lip is what distinguishes it from its close relative, brittlestem hempnettle (Galeopsis tetrahit). A true colonizer, it thrives on disturbed ground, roadsides, field margins, and damp waste areas, producing thousands of long-lived seeds per plant. It has a history of use in Tibetan and Buryat folk medicine and is being studied for antioxidant phenolic compounds, though reports on its toxicity are mixed.