Yikes! This Gorgeous Flower Is Actually An Invasive Weed You Don't Want In Your Yard

Oh, the mistakes we've made with importing non-native ground covers to the United States! Among the invasive garden plants to avoid is perhaps the most famous of them, kudzu (Pueraria montana var. lobata), which has taken over the South after being imported from Japan. English ivy (Hedera helix) might add a patina to college buildings, but it'll spread rapidly around in your garden. Less-known but no less invasive is yellow archangel (Lamium galeobdolon), a devil of a ground cover if there ever was one. Golden dead nettle might be its more appropriate common name, as it can smother native plants through its aggressive spreading nature. Weasel-snout is another less-than-flattering name. However, this plant has earned those epithets.

Yellow archangel is a shade-loving perennial that is considered invasive in parts of the Northeast, Upper Midwest, and Pacific Northwest. It can quickly grow up to 2 feet tall, form a dense mat, and alter the soil properties of forests. Being deer resistant and virtually disease and pest free, it faces few natural obstacles to its spread. Its upsides are merely its variegated leaves and small, pollinator-friendly yellow flowers – small compensation for the damage that it can do. In states like Washington, it is even illegal to buy, sell, or distribute yellow archangel.

The best way to prevent an invasion of yellow archangel is of course not to plant it in the first place. Like many species invasive in the United States, yellow archangel was introduced as an attractive garden plant and ground cover, then escaped into the wild. Ask your local garden center for native shade-friendly alternatives to yellow archangel such as barren strawberry (Waldsteinia fragarioides), Canada mayflower (Maianthemum canadense), or cranesbill (Geranium maculatum).

If you've found a few archangel plants in your garden, wait until after a rainy day — the best time to clear overgrown weeds – the to dig them out. Be sure to remove any and all portions of the plant. Don't throw your weeds into a compost pile or a garden waste pile. Yellow archangel can regrow from stems or seeds left behind or discarded, which is why it is often found growing rampant in areas adjacent to garden waste dumping sites. Place the weeds you've pulled in a sealable plastic bag, seal it tightly in order to kill the plant and any seeds, and dispose of as garbage so that you're not just sending your weed problem to someone else.

Yellow archangel spreads both by seed and by runners, so it's best to do your weeding in early spring before the plants flower and produce seeds. If your invasion is pervasive, however, you may need to smother the plants and deprive them of sunlight, just as you might do to kill tuberous rhizome weeds. Spread overlapping sheets of cardboard or newspaper over the affected area, then cover it with a mulch or compost mix 3 to 4 inches deep. Whatever you do, be vigilant and persistent.