Annabelle Hydrangea is a cultivated form of Hydrangea arborescens, a multi-stemmed deciduous shrub native to the eastern United States. It blooms in midsummer to early fall, with pale green flower heads that mature to white and age to ivory. The large flower heads are sometimes 12 inches wide. Because it blooms on new growth, it can be cultivated further north than most other hydrangeas. Annabelle is grown as a specimen plant, in a border, or as an informal hedge. Annabelle Hydrangea is easy to care for and is seldom troubled by pests.
Plant Annabelle Hydrangea in a location that receives morning sun and afternoon shade. In very cold regions, this shrub can tolerate full sun. In very warm regions, full shade is necessary. Annabelle is rated cold hardy in USDA zones 3 to 9 , and there are reports of the shrub growing in zone 2. It is heat tolerant in AHS heat zones 4 to 9.
Water Annabelle Hydrangea heavily once a week during the growing season if there has been less than one inch of rain. Mulch helps to retain moisture.
Add compost or other humus-rich matter to the soil each spring. Fertilize very sparingly with a balanced fertilizer.
Prune Annabelle Hydrangea during the winter while the shrub is dormant. In cold regions, the shrub may die back to the ground in the winter, so all the dead stems should be removed. In warm regions, pruning stems to 24 inches will encourage thicker stems.
Stake stems individually if the weight of the flower head is causing excessive drooping. Alternatively, surround the shrub with a 18-inch tall wire fence after pruning to support the new growth as it emerges.