Euphorbia palustris thrives in consistently moist soil. Water regularly to maintain dampness, especially during dry periods.

Avoid waterlogging, as this can lead to root rot, but do not allow the soil to dry out completely. Reduce watering slightly in cooler months but maintain a moist environment.

Prune Euphorbia palustris in late spring after flowering to maintain shape and remove spent flower stalks. Cut back stems to encourage bushier growth and prevent legginess.

Remove any dead, damaged, or crossing stems at any time of year. Wear gloves due to the milky sap.

Propagate Marsh Spurge from seed sown in autumn or early spring. Stem cuttings can also be taken in late spring or early summer. Allow the cuttings to callus for a few days before planting in moist, well-draining soil.

Use gloves when handling as the sap can be irritating.

Repot Euphorbia palustris every 2-3 years or when it becomes root-bound. Spring is the ideal time for repotting, just as new growth begins.

Use a pot that is only slightly larger than the current one and ensure the potting mix is well-draining, incorporating some sand or perlite. Water lightly after repotting.