Formosan Alder prefers consistent moisture and thrives in damp to wet conditions. Water regularly, especially during dry periods, ensuring the soil remains moist but not waterlogged.

Allow the top few centimeters of soil to dry slightly between waterings to prevent root rot. Good drainage is essential.

Prune Formosan Alder to maintain its shape, remove dead or diseased branches, and improve air circulation. The best time for pruning is during the dormant season, typically late winter.

Light pruning can be done after flowering to manage size and encourage bushier growth.

Propagation is typically done from seeds, which require stratification. Sow seeds in autumn in a cold frame or outdoors. Cuttings can also be taken from semi-hardwood in summer.

Ensure cuttings are treated with rooting hormone and kept in a moist, humid environment.

Repotting is generally not required for established trees in their natural habitat. For potted specimens, repot every 2-3 years in spring before new growth begins.

Use a well-draining potting mix and select a pot that is only slightly larger than the current one to avoid excessive root disturbance.