Nothing refreshes the eye in late summer like the cool, lush blossoms of hydrangeas. Their large, soft, multi-petaled flowers suit them for formal flower arrangements as well as casual bouquets. Available in an increasing variety of colors, hydrangeas serve as reliable perennial sources of beauty, even when weather becomes humid and dreary.
Select a sunny or partially-shaded area in your yard for best bloom performance. Hydrangeas tend to do best in moist, loamy soil and are shade tolerant. While hydrangeas grow in all temperate hardiness zones (4 through 7), fewer varieties are available in higher and lower temperature zones.
Plant your hydrangea in early spring or mid-fall to allow root systems to establish in cool soil. Good root development is important to hydrangeas, as to any long-lived perennial shrub.
Dig a hole twice the size and depth of the hydrangea's root ball or pot. Fill the hole with water to check drainage. If water is still standing in the hole 30 minutes later, dig an equal amount of peat-moss or shredded bark mulch into the soil you have removed from the hole. Use this soil mix to fill the hole, covering the top of the root ball to a depth of 1 to 2 inches.
Add a handful of aluminum sulfate or evergreen-friendly fertilizer to the soil mix if planting in the spring. Do not fertilize hydrangeas in the fall; this can stimulate growth that will be damaged by frost and freezing weather.
Water the plant thoroughly and tamp down the surrounding soil with your foot. This eliminates air spaces that may dry out and possibly kill root systems, and seats your plant securely.