Caring for a Pinky Winky hydrangea tree involves giving it enough sunlight, pruning away dead wood in the early spring and watering and fertilizing it appropriately. As Garden Smart points out, the Pinky Winky hydrangea is a variety of Hydrangea paniculata. It is an exceptionally hardy plant that can be grown as a shrub or tree.
Pinky Winky hydrangeas are shade-tolerant and do well when planted in the shadow of buildings or other trees. They typically need 4 to 6 hours of sun per day, requiring more sun in cooler climates. Too much afternoon sun can cause hydrangeas to wilt. If they do not recover overnight, they are receiving too much sun and must be moved from the area.
Pruning Pinky Winky hydrangeas causes them to produce more of their showy flowers. They do not require much pruning, but dead wood can be cleared away in early spring. Pruning should be done with 45-degree cuts made just above a bud.
Pinky Winky hydrangeas should be allowed to dry out before being watered again. They also should not be over-fertilized, since hydrangeas bloom better when slightly stressed. Balanced 10-10-10 or 16-16-16 fertilizers can be applied in early spring and late summer, though some gardeners never fertilize their hydrangeas. If a hydrangea isn't producing flowers, a high-phosphate 10-52-10 fertilizer may be needed. Also, a boost of liquid fertilizer in May or June often helps hydrangeas grow well.