Endless Summer is a trade name for a type of Hydrangea that was bred to bud on new growth and old wood. Previously, Hydrangeas needed a cold period to produce blooms on old wood and if there was any type of damage to the plant after budding, you could end up losing an entire season of flowers. The Endless Summer Hydrangeas will bloom the first spring to summer after planting and will give you up to three months more bloom time. These bushes are easy to grow, more cold-hardy than other Hydrangeas and are hardy in gardening zones 4 through 9.
Choose a location that has full sun to part afternoon shade. The farther north you are, the more sun the bush can handle. Southern locations should try to plant in a location that offers afternoon shade. Plan on planting bushes at least 3 to 6 feet from each other or other plants to give them plenty of room to grow.
Dig a hole 3 times the diameter of the root ball and 2 inches deeper. Amend the dug-out soil with a few handfuls of compost for a better draining and richer soil. Place 2 inches of the amended soil back in the hole so that when you place the plant, it will be at the same level it is in the container you purchased it in.
Carefully remove the plant from the container and rinse off most of the soil attached to the roots. Place the plant in the hole and cover 1 inch of the root ball with amended soil. Water in the soil to compact it around the root ball and then continue with more soil and water until the hole is completely filled in and level with the surrounding soil.
Water the plant, soaking the soil three times a week for the first two weeks. Then cut back the watering to twice a week through the summer. In the fall, keep the soil moist until the first frost and then discontinue watering until spring.
Apply a 10-40-10 fertilizer only after you start to see growth in the spring and then again in mid-summer. Follow manufacturer's suggestions on amount of fertilizer to use. Do not fertilize the Hydrangea after August.
Mulch around the plant in the spring to help retain moisture and keep weeds away. Use a shredded bark type mulch and in late fall to early winter, place mulch around the crown of the plant to protect it from the winter frosts. Remember to remove it in the spring before you start to water heavily.
Prune off flowers as they start to die to promote new blooms. You may want to leave the dead flowers on the plant in fall through the winter to help insulate the new buds, but prune them off in the spring. Prune to shape in the spring, but the Endless Summer really doesn't need pruning for health or blooming purposes.