UT Gardens' Plant of the Month: Hydrangea

Submitted by Amanda Hannah

No shrub says “Southern Garden” more than the hydrangea. These beautiful plants have long been a staple in our region, and for good reason. Hydrangeas include a large variety of cultivars with many different growth habits and cultural needs. One selection, Hydrangea macrophylla 'Bailmer', is commonly known as the ‘Endless Summer Hydrangea’.

This beautiful cultivar was discovered by Dr. Michael Dirr, of the University of Georgia , at Bailey Nurseries in Minnesota . Unlike most hydrangeas, Endless Summer blooms on both old and new wood. This allows for blooms all summer long, hence the name. It is also unusually hardy and can be planted into cold hardiness zone 4.

Endless Summer prefers to be planted in a moist but well-drained location that receives morning sun and afternoon shade or partial shade. It grows 3-5’ tall and wide and can be pruned at almost any time because of its blooming habit. The exception to this is that young plants should not be pruned until they have had a chance to get established.

Like most mop head hydrangeas, the flower color of Endless Summer depends on the acidity of the soil in which it is planted. It will produce pink blooms in alkaline soils (aim for a pH of 6.0-6.2) and blue blooms in acidic soils (pH below 5.2-5.5). Depending on your climate, this plant will start blooming as early as June and not stop until October.

These plants make nice foundation plantings or great accent plants and they will brighten up any shady spot in which they are placed. The huge blooms also make attractive cut or dried flowers.

Amanda Hannah is an undergraduate student in the University of Tennessee Department of Plant Sciences. She works as a UT Gardens Intern under the guidance of Dr. Susan Hamilton, director of the UT Gardens. The UT Gardens are a project of the Tennessee Agricultural Experiment Station. The original gardens are located in Knoxville on Neyland Drive . Additional gardens are located in Jackson on Airways Blvd. Admission is free, and the Gardens are open to the public seven days a week during daylight hours.

Contact:

Patricia C. McDaniels, (865) 974-7141