Ulleungdo hemlock prefers consistently moist soil. Water deeply when the top few centimeters feel dry. Avoid waterlogging, as this can lead to root rot. During dry spells, increase watering frequency.

In winter, reduce watering, allowing the soil to dry out slightly between waterings.

Prune Ulleungdo hemlock to maintain shape or remove dead, damaged, or crossing branches. The best time is late winter or early spring before new growth begins. Light pruning can be done in summer.

Avoid heavy pruning, which can stress the tree.

Propagation of Ulleungdo hemlock is typically done by seed or cuttings. Seeds require stratification. Cuttings are best taken in late summer or early fall from semi-hardwood.

Use rooting hormone and provide consistent moisture and high humidity for best results.

Repot young Ulleungdo hemlock plants every 2-3 years in early spring before new growth starts. Use a well-draining, acidic potting mix. Ensure the new pot is only slightly larger than the current one.

Mature trees rarely need repotting.