Hydrangea plants are perennial and are used as cut-flower arrangements. They come in a vast array of colors. The best time to plant new Hydrangea is in early summer. The best time to transplant dormant Hydrangea plants is early fall, before the first frost. Hydrangeas can withstand planting zones 4 to 6 but do best in planting zones 7 to 10.
Choose a partially-sunny location with well-drained soil to plant the hydrangeas. Make certain there is at least 6 inches of space available between the hydrangea plants and other foliage.
Measure the size of the hydrangea pot and dig a hole twice the size of the original hydrangea container. The hole should be 6 inches deeper than the height of the hydrangea and the root ball.
Place the dirt from the hole into a large bucket or wheel barrow. Estimate roughly how much dirt you have. Add one part pine mulch bark to three parts dirt and mix well. Add one part rough composting material to four parts of the mixture. Mix well.
Prune all the leaves off the hydrangea plant at the base. Move upward pruning leaves for 2 inches. If the hydrangea is not in bloom and looks thin, prune all the leaves and just leave the nodes.
Turn the original hydrangea plant container upside and give the plant a tug at the base of the root stem to remove it from the container. Break apart the root ball with your fingers to encourage and stimulate plant growth.
Fill in the planting hole with 3 inches of the mixture from Step 4. Set the hydrangea plant on top of the mixture. Continue filling the hole with the mixture until the entire root ball is covered. Only 1/2-inch or less of the hydrangea's plant stem should be covered with dirt.
Water the newly-planted hydrangea plant until the dirt is very moist. Add a small amount of additional water after the initial amount has soaked into the ground and roots of the hydrangea plant.