It is best to plant hydrangea bushes in either the spring or fall, according to the Farmer's Almanac. The flowers bloom in the late summer to early fall.
Planting a hydrangea bush is a relatively easy task. These plants prefer a rich, somewhat moist soil and grow and bloom in partial shade. To plant a hydrangea, dig a hole as deep as the root ball and approximately two to three times as wide. Set the root ball in the hole and fill it halfway with soil, water it thoroughly, add the rest of the soil and water it again. It is important that these plants receive plenty of water in the first couple of years and afterward bloom regularly in the summer or early fall.