Motherwort

How to recognise it

Growth habit

Upright, clump-forming perennial 50–120 cm tall, with square, often reddish-brown and slightly hairy stems.

Leaf

Opposite and stalked. The lower leaves are palmately divided into 3–5 deep, toothed lobes, the ones above are three-lobed and the topmost narrow and almost undivided.

Flower

Small two-lipped flowers about 1 cm long, pale pink to lilac, in dense whorls in the leaf axils along the upper part of the stem. The upper lip is white and woolly outside.

Fruit/Seed

Four three-sided nutlets in a calyx with five stiff, spiny teeth that harden after flowering and prick.

Roots

Short, woody rootstock; the plant forms a solid clump but does not spread aggressively.

Confusion with

Black horehound and dead-nettles have undivided, oval leaves. Hemp-nettles have swollen stem nodes and undivided leaves. Motherwort is recognised by its deeply palmately lobed lower leaves and prickly calyx teeth.

Flowering: June–September · Pruning: March and September

Why grow it?

• Flowers from June to September and attracts bumblebees, honeybees and other long-tongued bees.
• A piece of cultural history: once found in every monastery garden, it is now a rare heritage plant of old village centres.
• An upright, sturdy plant that gives structure to a wild border or herb garden.
• The dry stems with their calyces stay standing in winter and give shelter to insects.
• It was used historically as a medicinal herb, among other things for complaints attributed to the heart; hence the scientific name cardiaca.

Motherwort: where does it grow best?

• In the wild on waste ground, near farms and old walls, on dykes and along hedges and woodland edges, often on chalky, rich soil.
• Sun to partial shade.
• Ordinary, well-drained garden soil; it copes reasonably well with drought but dislikes wet feet.
• In the garden: in a herb garden, a wild border or a rough strip along a wall or shed.

Goes well with

• Wild marjoram: Another member of the mint family for bees and butterflies, low at its feet.
• Feverfew: Small white daisies as a contrast, also an old plant of monastery and farm gardens.
• Common valerian: Tall, with pale pink umbels; it suits the feel of an old village garden.
• Chicory: Blue flowers in the same summer period, on the same sunny, chalky soil.

Motherwort: when and how to plant it?

1. Buy a plant from a native plant or herb nursery, or sow seed from a nursery or from your own garden.
2. Sow outdoors in September–October, in a tray or where it is to grow: the seed germinates better after a cold spell. Spring sowing is possible, but germination is then more erratic.
3. Plant in March–April or in October, 40–50 cm apart, at the same depth as in the pot.
4. Water after planting, and again in dry spells during the first weeks.
5. One plant is enough to start with: it self-seeds.
6. Never take plants from the wild: motherwort is rare in Belgium.

Care

Watering

Only in the first year during drought; after that it looks after itself.

Feeding

Not needed. On very poor sandy soil a little compost in spring is enough.

Support

On rich soil or in shade it may flop. A few twiggy sticks as support or a place among other sturdy plants helps.

Self-seeding

Leave a few stems for the birds and for seedlings; cut the rest after flowering if you don’t want too many young plants.

Spreading

Its roots do not run, but it self-seeds. Weed out surplus seedlings in spring.

Tip: Give motherwort a place against a sunny wall or shed at the back of a herb garden: that shows off its old village character best, and the calyces prick nobody.

Pruning and mowing

Pruning months: March and September.

When: Leave the stems over winter and cut them down in March, before the new shoots appear. If you want fewer seedlings, cut some back in September.

How:

• Cut the old stems down to just above the ground in March.
• For fewer seedlings, cut back some of the faded stems in September, before the seed drops.
• Lay the cut stems in bundles in a quiet corner: insects overwintering inside can still crawl out.

Caution: Wear gloves: the spiny calyx teeth on the faded stems prick.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Seed

Sow outdoors in autumn; the seed germinates in spring. Seedlings often flower in their second year.

Division

Divide older clumps with a spade in March or October and replant at once.

Motherwort: how does it get through the winter?

Hardy to −25 °C.

• The parts above ground die back; the plant overwinters as a rootstock, sometimes with a small rosette of young leaves.
• Fully hardy.
• The dry stems with calyces stay standing and look lovely with frost on them; insects overwinter in them and birds search them for seed.

Diseases and pests

• Self-seeding: It can produce lots of seedlings. Cut back some of the flowering stems after flowering and weed in spring.
• Prickly calyces: The spiny calyces catch in clothes and in animal fur. Wear gloves when tidying and don’t plant it right next to a path.
• Aphids: Sometimes on young shoots. Ladybirds, hoverfly larvae and birds usually clear them up.
• Flopping: On soil that is too rich or in too much shade. Plant it in sun and don’t feed.

Through the year

• March: Cut down old stems. Divide or plant clumps.
• April: New shoots. Weed out or move seedlings.
• May: The stems grow fast; support if needed.
• June: Flowering begins.
• July: Full flower. Bumblebees and bees on the flower whorls.
• August: Flowering. Water young plants during drought.
• September: Last flowers. Cut back some stems to prevent too many seedlings. Collect seed.
• October: Sow outdoors. Plant or divide.
• December: Leave dry stems standing for insects and birds.

Did you know?

• Leonurus means ‘lion’s tail’ in Greek, after the long flower spikes with their whorls of flowers.
• The names cardiaca and the Dutch hartgespan come from old folk medicine: the plant was once used for complaints attributed to the heart. The English name motherwort refers to its former use for women’s ailments.
• Motherwort has followed people for a long time: you still often find it where a farm, monastery or castle has stood for centuries.