“It this a perennial or is it a weed?”
Customers frequently come into our store in Hyannis with bunches of foliage and ask that question. Early in the season it’s sometimes hard to tell which plants are desirable perennials and which ones are unwanted weeds. One of the plants that frequently fools gardeners is mugwort (Artemisia vulgaris), a persistent and invasive weed with foliage that looks like mums. If you have mugwort, you’ll want to dig it out as quickly as possible and continue the prompt removal of returning shoots. Here is a pictorial to help you know if mugwort has invaded your garden.
There are three different species of plants in this small group and they are very similar. It's no wonder that gardeners get confused!
This is a leaf from a perennial chrysanthemum (aka Dendranthema) The image on the left shows the underside of the leaves, and the image on the right is right-side-up.
This is mugwort foliage. Notice how the leaves are more pointed. One easy way to tell mugwort from other perennials and weeds is by looking at the underside of the leaf: the images on the left and the bottom right corner are of the underside, which is more silver or gray in color. The greener leaves are the top side of the foliage.
Here is a plant that's similar to mugwort that's often found in perennial gardens. This is feverfew (Tanacetum parthenium), a self-seeding biennial that has little white daisy flowers in June and early July. Many gardeners leave some young plants where they want them but pull the unwanted and excess seedlings out. This is a plant that requires a gardener's controlling hand!