Water Cassinia denticulata moderately, allowing the soil to dry slightly between waterings. Avoid waterlogging, especially in cooler months. Established plants are quite drought-tolerant.

Reduce watering significantly during winter dormancy to prevent root rot.

Prune in late spring or early summer after flowering to maintain shape and encourage bushier growth. Remove dead or damaged stems at any time.

Light pruning can be done to control size, but avoid cutting back into old wood, as it may not regrow well. Deadhead spent flowers.

Propagate from semi-hardwood cuttings taken in summer. Select healthy, non-flowering shoots, dip the base in rooting hormone, and insert into a well-draining potting mix. Maintain consistent moisture and warmth.

Alternatively, propagate from seed sown in autumn or spring in a cool, moist environment.

Repot established plants every 2-3 years, or when root-bound, preferably in early spring before new growth begins. Use a well-draining compost mix, such as loam-based compost with added grit.

Choose a pot one size larger than the current one to allow for root expansion.