Hydrangeas

Hydrangeas include woody shrubs and self-clinging climbers known for clusters that combine small fertile flowers with larger, showy florets. Their mature size, hardiness, flower color and pruning needs vary by species and cultivar, so choose and care for the exact hydrangea type rather than applying one rule to the whole genus. ## Site and water Most landscape hydrangeas grow best in fertile, organic-rich soil that holds moisture while draining well. Keep plants watered during hot, dry weather, and match light to the type: many bloom best with several hours of sun, while some tolerate or prefer afternoon shade. The genus ranges from compact shrubs to tall climbers; check the selected plant's mature dimensions and local hardiness range before planting. [UConn's hydrangea guide](https://homegarden.cahnr.uconn.edu/factsheets/hydrangea/) describes these differences among common garden types. ## Flowering and pruning Hydrangeas do not all flower on the same year's growth. Smooth hydrangeas such as Annabelle form flower buds on new wood and can be pruned in fall, winter or early spring; climbing hydrangea blooms on older wood and is pruned after flowering. Bigleaf hydrangea has a different pruning window. Identify the type before cutting so you do not remove the next season's buds. ## Maintenance Water deeply during dry spells, mulch to moderate soil moisture, and remove dead or damaged stems as appropriate for the selected type. Use a type-specific pruning schedule; avoid heavy, untimed pruning because it can reduce flowering.