Identification

• Hydrangeas were wildwood plants before they moved into backyards and gardens. Today, some 23 varieties grow around the world. Hydrangea macrophylla takes the number one spot in the United States. Known as bigleaf or French hydrangea, this popular species offers big, rounded clusters of blossoms; each flower head includes some showy blooms and some inconspicuous flowers. Bigleaf -- as well as most other types of hydrangeas -- requires moist soil and regular water to thrive.
  
  

Planting

• Although hydrangeas prefer partial shade to full sun, they require some sunlight to produce their gaudy blossoms. The ideal hydrangea placement provides the plant morning sun and afternoon shade. Alternatively, all-day dappled sunlight appeals to this shrub. In full sun, the beautiful sky-blue and deep pink blossoms fade into pastels, flowers and leaves may wilt and, in extreme heat, the hydrangea can die. In especially sunny placements, hydrangeas require additional water.
  
  

Soil

• Most gardeners know that hydrangea flowers change color depending on the acidity of the soil. A plant that offers pink flower clusters in alkaline soil will bear blue blossoms in acidic soil. More important for the health of the flower is soil drainage. Although hydrangeas love moist soil, if the soil is clay or marshy -- trapping water around the plant roots -- the hydrangea develops root rot and dies.
  
  

Water

• If your usually perky hydrangea leaves droop, pull out the watering can. Hydrangeas need regular water during the growing season -- spring through autumn -- and show their distress if they do not get enough. During hot days or periods of drought, their water requirements rise. Ohio State University horticulturists recommend applying mulch to help hydrangeas retain water. Gardeners in hot climates compensate for excess sun and heat by watering the plants more frequently.