Mugwort plant: how to recognise, plant and care for it

Mugwort (Artemisia vulgaris) is a native perennial plant with deeply cut leaves, dark green above and white underneath. The stems grow 0.6 to 1.5 metres tall. From July to September they carry plumes of tiny, inconspicuous flower heads. Mugwort wants sun and soil rich in nutrients.

Mugwort at a glance

Leaf

April to October

Flower

July to September

Fruit

no noticeable fruit

JanFebMarAprMayJunJulAugSepOctNovDec

How do I recognise mugwort?

Start with the leaves. Each leaf is deeply cut, like a feather, into narrow pointed lobes. The upper side is dark green and almost hairless. Turn a leaf over and the underside is white and felted. A bruised leaf gives off a faint herbal scent.

The stems are tough, grooved and red to purple-red, right up to the top. They feel slightly woody, so this herbaceous plant looks a little like a shrub. At the top sit richly branched plumes full of egg-shaped heads of 3 to 4 millimetres. There are no petals to see: each head is made of tiny tubular florets.

A relative looks similar: wormwood (Artemisia absinthium). Its leaves are grey and silky-felted on both sides. Wormwood also has round heads that droop slightly and flower lemon-yellow. On mugwort only the underside of the leaf is white, and the heads stand upright.

Where does mugwort grow best?

Mugwort grows best in full sun: more than six hours of direct sun a day in summer. Three to six hours works too. The soil can be dry or moist, as long as it is rich in nutrients. In the wild, mugwort grows on dikes, on road verges and on waste ground.

In a garden, these spots cause trouble:

• Under a dense canopy of leaves. The sun reaches the ground there for less than two hours, and mugwort wants an open, light spot.
• In soil that stays wet in winter. The roots want soil where water drains away well.
• At the front of a small border. Mugwort towers over low neighbours and blocks their light.

In winter, little of the plant is left above ground. After an autumn cut, only short stubs show. In spring, new stems come up from the underground rhizomes.

AugustJanuaryThe same border in August and in January. This is a generated image, not a photograph.

A tall plant like mugwort belongs at the back of the border. In the app you can see how deep that border can be in your garden: your own plot to scale, with the buildings around it, and you draw the border on it yourself.

Planting and caring for mugwort

Mugwort is sold as a young plant in a small pot, or as seed. Dutch nurseries label it bijvoet. A potted plant can go into the ground whenever the soil is neither frozen nor waterlogged. Water it in well afterwards, even when the soil is already moist. After a summer planting, keep the soil moist for the first few weeks.

Space the plants about 40 centimetres apart: 5 to 7 per square metre. On planting day that looks generous. After a few years the plants grow together into one dense mass.

The nesting season runs roughly from March through July. Birds with several broods carry on into August. When you cut in those months, first check for a nest among the stems.

What goes wrong with mugwort?

Young mugwort seedlings come up all over the border. The plant self-seeds. Cut off the plumes after flowering, before the seed ripens. Pull out the seedlings while they are small.

The clump gets wider every year. Mugwort spreads through woody underground rhizomes. In spring or autumn, slice off part of the clump with a spade and replant only one piece.

You see no flowers. They are there, but so small that they are easy to miss. The grey-green plumes at the top of the stems are the flowers.

The plant suddenly dies in a hot, dry summer. That can be honey fungus, a fungus that attacks the roots. Between the bark and the wood of the roots you then find a white sheet of fungus. Dig up the plant with all its roots and throw it away, but not on the compost heap.

Beyond that, mugwort rarely has trouble with pests.

Which insects and birds use mugwort?

Mugwort is wind-pollinated: the wind spreads the pollen. Even so, many insects visit the plant and use it as food. One of them is the caterpillar of the tawny speckled pug (Eupithecia icterata), a small moth. That caterpillar feeds mainly on yarrow, but eats mugwort too.

Nothing about birds on mugwort has been described with certainty.

Is mugwort poisonous?

Mugwort is not known as a poisonous plant in the garden. In some people, though, touching the plant causes skin inflammation: red, irritated skin.