How To Care For Easter Hydrangea. The main way people kill a greenhouse grown Hydrangea is by letting it get too dry. Water the hydrangea frequently so that the soil is moist but not saturated hydrangeas require soil that is moist yet well draining so that the roots do not sit in boggy soil and rot.
An unheated room is ideal. Dig a hole as deep as the root ball and 2-3 times as wide. Panicle hydrangea Hydrangea paniculata grows in USDA zones 4 to 7 while smooth hydrangea Hydrangea arborescens thrives in zones 4 to 9.
Place a bit of alum powder on a plate about 1 2 in 13 cm deep.
Gently loosen the roots then plant using plenty of rich soil. Although the hydrangeas leaves and flowers appear delicate they actually dont require a lot of tender care. Dig a hole as deep as the root ball and 2-3 times as wide. Oakleaf hydrangea Hydrangea quercifolia is hardy in zones 5 and 9.