the Endless Summer is a Bigleaf Hydrangea (Hydrangea macrophylla) that blooms on both new and old wood. The best time to prune Hydrangea is in the late winter or early spring by removing the oldest stems. The youngest stems will be light brown in color with no side branches – they should always be left, as they will yield the largest flowers. Stems that are older than one year are gray in color and are branched. After four to six years of growth, these older stems produce smaller flowers and should be cut back to 1–2” above the ground along with any dead stems, stimulating the production of new stems from the base. For the Endless Summer Series, it is still best to thin the plant and remove the oldest and least productive stems. You can reduce plant size by pruning them immediately after flowering by cutting stems to a pair of healthy buds.

The following article provides more information on Hydrangea care: Pruning hydrangeas | UMN Extension

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