Diplazium amamianum prefers consistently moist soil. Water thoroughly when the top centimeter of soil begins to feel dry. Avoid letting the plant sit in waterlogged conditions, as this can lead to root rot.

Reduce watering slightly during cooler months, but never allow the soil to dry out completely.

Pruning is generally minimal for Diplazium amamianum. Remove any dead, damaged, or yellowing fronds by cutting them at the base with clean, sharp shears.

This helps maintain the plant's aesthetic appeal and prevents potential disease. Pruning can be done anytime unwanted fronds appear.

Diplazium amamianum can be propagated by division or spores. Division is best done in spring when new growth emerges.

Carefully separate sections of the rhizome, ensuring each piece has healthy roots and at least one frond. Spore propagation is more challenging and requires specific conditions.

Repot Diplazium amamianum every 2-3 years, or when it becomes root-bound. Use a well-draining potting mix, such as a blend of peat moss, perlite, and compost. Choose a pot that is slightly larger than the current one.

Repotting is best performed in spring before active growth begins.