In either tropical or temperate climates, hydrangeas are considered a full shade shrub, although at least a few hours of direct on any variety will result in deeper root development and increased flower bud development, which equals more blooms. Hydrangeas can tolerate full sun, although their water needs will be increased, and their large leaves may wilt during the day if moisture is insufficient. Water regularly, especially until established, but avoid watering in the evening as this promotes a leaf spot, especially on oakleaf and macrophylla varieties.
Pruning depends on which type of Hydrangea you have. Bigleaf Hydrangea – Hydrangea macrophylla. This species of hydrangea has blue or pink flowers, depending on the acidity of the soil. Add lime for pink blooms or add aluminum sulfate for blue as the mineral aluminum is what makes them blue. 2 applications are recommended per year in high ph soils or next to masonary foundations. This species acts as a perennial here, dying to the ground each year. They should be cut close to the ground in late fall. The older varieties of bigleaf hydrangeas do not bloom reliably here as they set flower buds on old wood that dies each year. The newer varieties regrow from the ground and bloom reliably and may rebloom again, as long as culture conditions are met.