Water consistently, keeping the soil moist but not waterlogged. Allow the top inch of soil to dry out between waterings, especially during dry periods. Reduce watering in cooler months to prevent root rot.

Ensure good drainage to avoid issues.

Deadheading spent flowers can encourage more blooms and prevent self-seeding if unwanted. Trim back leggy growth in mid-summer to promote a bushier habit.

Remove any dead or diseased stems as needed to maintain plant health.

This plant readily self-seeds. For controlled propagation, sow seeds in early spring directly into the garden or start indoors a few weeks prior. Cuttings can also be taken in late spring or early summer.

Galeopsis angustifolia is often grown as an annual or self-seeds readily, so repotting established plants is rarely necessary. If growing in containers and a plant becomes root-bound, repot into a slightly larger container in spring.