Keep the soil consistently moist but not waterlogged, especially during warmer months and when the plant is establishing. Reduce watering slightly in winter.

Avoid letting the soil dry out completely, as this can stress the plant and impact flowering. Water at the base to prevent fungal issues on foliage.

Prune immediately after flowering to shape the plant and remove any dead, damaged, or crossing branches. Avoid heavy pruning in late summer or fall, as this can remove flower buds for the following year.

Light pruning can be done to maintain size and form.

Grafting is the most reliable method for Rhododendron yedoense. Softwood cuttings can be taken in early summer and rooted under mist with bottom heat, though success rates can be variable.

Layering is another option, though it takes longer to establish.

Repot young plants every 2-3 years into a slightly larger container using an acidic, well-draining potting mix. Mature plants rarely need repotting and prefer to be established in the ground.

Ensure the new pot has adequate drainage holes and avoid planting too deeply.