Enkianthus

Fertilizing

Apply liquid fertilizer every two weeks during spring and summer growth periods, being particularly mindful not to overfeed. In early spring, supplement with potassium and phosphorus fertilizers specifically to promote flowering. The soil pH can be balanced with occasional ericaceous feed applications, as these trees have high fertilizer requirements but can be damaged by excess feeding.

Placement

Position the tree in full sun during spring and autumn for optimal growth and fall coloration. During summer, move to a partially shaded location to protect from intense heat. Enkianthus are frost-hardy down to -5°C (23°F) but prefer temperatures between 15-25°C (59-77°F) during the growing season. Protect from strong autumn winds to preserve the vibrant fall foliage colors.

Pruning

Allow natural growth during the flowering season, then perform hard pruning after flowers fade. Trim new shoots throughout the growing season, with sub-branch pruning in summer and main branch pruning in September. Take extra care with larger cuts as these trees heal slowly. Winter is ideal for wiring when leaves have fallen, making branch structure more visible. Wire can create various styles including twin-trunk, slanting, and informal upright - but avoid formal upright, cascade, and broom styles.

Repotting

Repot annually in early spring before buds begin to break, though more mature specimens can go 2-4 years between repottings. Use a well-draining soil mix with pH 5-6, combining peat, river sand, and heath mold. Since Enkianthus is extremely lime-intolerant, ensure any stones or grit in the soil mix are thoroughly washed to remove lime traces. When repotting, trim roots conservatively and avoid major root mass reduction.

Watering

Water daily during the growing season, increasing frequency when leaves are developing. Maintain consistently moist but not soggy soil conditions. Reduce watering in autumn and winter months. These deciduous trees need substantial water but are susceptible to root rot, so ensure proper drainage and avoid overwatering. The soil should be slightly dry before the next watering.

References

Bonsai Tree Gardener Miyagi Bonsai Scottish Bonsai Association