Water Japanese Bluestar regularly, especially during its first year and dry periods. Ensure the soil remains consistently moist but not waterlogged. Reduce watering in late fall and winter as the plant enters dormancy.

Overwatering can lead to root rot, so good drainage is essential.

Prune Japanese Bluestar after flowering to maintain a tidy shape and encourage a second flush of blooms. Cut back the stems by about one-third to one-half. Remove any dead, damaged, or crossing branches at any time.

This also prevents the plant from becoming leggy.

Propagate Japanese Bluestar from seed sown in autumn or early spring. Alternatively, take softwood cuttings in late spring or early summer. Root cuttings in moist, well-draining potting mix.

Division of established clumps in spring is also an effective method for increasing plants.

Repot young Japanese Bluestar plants every 2-3 years in spring or early autumn. Established plants generally prefer to be left undisturbed.

Choose a pot that is only slightly larger than the current one, ensuring adequate drainage holes. Use a good quality, well-draining potting mix.