White ash prefers consistently moist soil, especially when young. Water deeply once a week during dry periods, ensuring the soil is well-drained to prevent root rot.

Mature trees are more drought-tolerant but benefit from supplemental watering during extended dry spells to maintain optimal health and vigor.

Prune white ash to shape young trees and remove dead, damaged, or crossing branches. Timing is best in late winter or early spring before sap flow begins. Avoid heavy pruning in summer as it can attract borers.

Maintain a strong central leader for a well-structured mature tree.

White ash can be propagated from seed, typically sown in the fall for stratification. Cuttings are less common and can be challenging to root.

Grafting is also a possibility for specific cultivars, but most trees are grown from seed or by transplanting nursery-grown stock.

Repotting is generally not applicable to white ash as it is typically planted as a large nursery stock or directly seeded. If a young tree is container-grown, repot into a larger container when root-bound, usually every 1-2 years, using well-draining soil, before its final outdoor planting.