I planted a hydrangea this spring. It looked good for a while but now it has stems with seeds. It has actually bloomed. Can you help me?
This is not the complete answer, but Hydrangeas need to be in either Ericaceous compost or acid soil. The level of acid will determine the colour of the flowers. They do not like frost, and should be pruned by simply removing the flowerhead once it has died off and then a gentle prune to maintain the size and shape you want.