Originally published in The Garden Path, Spring 2024.  If you would like to get The Garden Path, we invite you to JOIN US as a member.

The perennial plant Urtica dioica (UR-ti-kuhdi-O-ee-kuh), often known as Common or Stinging Nettle, may conjure up unpleasantries if one has ever accidentally brushed up against its green saw-toothed margined leaves or wiry, fairly square stems. The plant has many hollow hairs called trichomes that, upon contact, inject chemicals causing a stinging sensation. Ouch!

These were my exact thoughts in late May of last year when I discovered a healthy, large plant growing in the dappled sunlight beneath my overgrown Arrowwood Viburnum. Since I had not planted it there, my knee-jerk reaction was to yank out the noxious ‘weed’! But then I noticed that multiple leaves were folded together, as indicated on the image. What could possibly be able to touch this plant to work to accomplish such a task?I needed to find out; the plant was safe, for now.

My research led me to discover that Stinging Nettle is the primary host plant for the common Red Admiral (Vanessa atalanta) butterfly. These butterflies are migratory, so they arrive in spring, mate and then the female lays her eggs on nettle plants. Tiny spiny caterpillars emerge, eating the plant and continuing to grow. To avoid predatory consumption, they seek protection by camouflaging themselves within the confines of a folded leaf.Later, underneath a leaf, the caterpillar will hang upside down and metamorph into a hanging chrysalis that looks like a dead leaf. Amazing!

The mystery was solved. The caterpillars themselves were the ones folding the leaves!But a question still remained. How could they withstand the trichome injections? Upon further investigation, it was made known that these hairs are most abundant on the stems, leaf petioles and the undersides of the leaves. Ahh…they were using the top of the leaves.

Furthermore, I learned that I too had benefited from the knowledge of the plant’s discovered location. Nettles prefer to grow in areas of high soil fertility, especially phosphate and nitrate; it is an indicator to gardeners as to the quality of the soil. Wow! Here in existence was living proof of successful organic amendment efforts.

My attitude had changed from one of detest to that of admiration. The plant would be permitted to remain. How could it not?