Hydrangeas are perennial bushes that produce giant blooms in mid-summer. Native to North and South America, the Himalayas, and part of Asia, these deciduous shrubs require partial shade and slightly acidic, moist soil. Non-bloom producing shrubs may be attributed to several factors that can be easily addressed.
A harsh winter or summer is the most common reason blooms fail to appear on a hydrangea. Most hydrangea plants generate buds the year before they bloom. Frost may kill most of the winter foliage and destroy the buds on the branches. If temperatures are too warm, the plant will not flower and the buds can fall off. Fresh growth comes in the spring and summer for the next years flowering season.
Hydrangea plants need abundant amounts of water and nutrients to form buds that mature into flowers. Rich compost and mulch should be added to the plant base yearly to replenish nutrients in the soil. Hydrangeas require slightly acidic soil with ample drainage. The roots should be kept moist throughout the growing season to encourage lush flowers.
Pruning in fall, winter, or spring can sever newly formed buds causing the plant not to bloom the following summer. Hydrangeas, such as the Smooth Hydrangea, flower from current years growth. Lack of pruning the Smooth Hydrangea can cause the plant to become very bushy with minimal colorful flowers. The plant should be pruned in fall immediately after the blooms have faded.