Bridge Gardens’ Weed of the Month | Mugwort (Artemesia vulgaris)

September 14, 2023

By Rick Bogusch

Bridge Gardens

Most of you know the dreaded mugwort. You probably have it somewhere on your property or have seen it in masses along roads and major highways.

Chrysanthemum-like leaves cover the dark stems of this 2.5-foot member of the daisy family. Flowers are petal-less, yellowish, and inconspicuous, not daisy-like at all, and appear in clusters at the tops of stems. These become single, brown, grain-like seeds.

Mugwort spreads by seed but spreads most aggressively by horizontal underground stems or rhizomes. These can form large, fast-spreading colonies that are almost impossible to eradicate, even if you resort to herbicides.

What You Should Do Now:

Non-toxic controls are primarily mechanical:

  1. Prevent seed dispersal by mowing in the first two weeks of September, when mugwort seed is still immature and not viable.
  2. Since mugwort spreads aggressively underground, hand-pulling in spring and early summer, before underground roots form, can control populations and keep them from spreading.
  3. Landscape fabrics, tarps and other impenetrable coverings can be used to smother mugwort colonies, but it can take more than a season.
  4. Avoid patches of bare ground where mugwort seed can sprout and form new colonies. Sow grass seed or cover crops to stop mugwort from getting started. Perhaps the most effective way of preventing mugwort from taking over your gardens and property is to use a variety of methods simultaneously and repeatedly.

Consistency and persistence are keys to keeping this invasive under control.

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