How to Grow Motherwort
Leonurus cardiaca
Motherwort is a tough, low-maintenance perennial that thrives in poor soil and tolerates shade. Plant in spring or autumn, spacing 45 cm apart. It forms a rosette of deeply lobed leaves in its first year, then sends up tall square stems bearing whorls of small pink-purple flowers from midsummer. Deadhead promptly after flowering to prevent aggressive self-seeding — a single plant can colonise a border quickly. Cut back by one-third after the main flush to encourage a second flowering. In late autumn, cut to the ground and mulch lightly. Divide congested clumps every three to four years in spring.
Yearly Lifecycle
Care Essentials
Rarely needed. Motherwort thrives in poor to average soil — rich feeding encourages excessive leafy growth at the expense of medicinal potency. A light top-dressing of compost in early spring is sufficient.
Watch For
- Powdery mildew in humid conditions
- Slugs on young spring growth
- Self-seeding (can become invasive)
Companions
Valerian, Echinacea, Yarrow, Calendula
Care Requirements
Light
Full sun to partial shade
Produces most flowers and sturdiest stems in full sun. Grows in part shade but becomes tall and floppy with sparse flowering in deep shade.
Watering
Drought-tolerant once established
Tolerates dry conditions well once established. Water young plants until they settle in. Avoid waterlogged soil which promotes root rot.
Fertilizing
Rarely needed, poor soil preferred
Thrives in poor to average soil. Rich feeding produces excessive floppy growth at the expense of medicinal potency. A light compost top-dressing in spring is sufficient.
Pruning
Cut back after flowering, to ground in autumn
Cut stems by one-third after the main flush to encourage a second flowering and prevent self-seeding. Cut to ground level in late autumn. Wear gloves as the seed heads have sharp bristles.
Growing Tips
Deadhead to control spread
Motherwort self-seeds prolifically. Remove spent flower spikes before seeds set unless you want it to naturalise. A single unmanaged plant can fill a border within two seasons.
Poor soil is fine
Resist the urge to feed or improve the soil heavily. Motherwort produces more potent foliage and a tidier habit in lean conditions. Rich soil results in floppy, oversized growth.
Shade tolerant but flowers best in sun
Motherwort will grow in part shade but produces the most flowers and the sturdiest stems in full sun. In deep shade it becomes tall and floppy with sparse flowering.
Wear gloves when cutting back
The mature seed heads have sharp, hooked bristles that attach to skin and clothing. Always wear gloves when cutting back after flowering.
