The blues, pinks and whites of hydrangea blooms are ubiquitous in home gardens. Hydrangeas are easy to maintain and their vividly coloured flowers can nearly cover the bush. There are many types of hydrangeas, even some climbing varieties, but probably the most well-known is what is called the French hydrangea (Hydrangea macrophylla) or mopheads. This plant is also nicknamed big-leaved hydrangea.
In Latin, hydra means water, an indication of a requirement for these large-leaved plants. Hydrangeas need steady watering in summer to prevent leaves and flowers from wilting. Water hydrangeas as much as it takes to keep them from wilting; for the most part, this means watering once or twice or week, perhaps more during periods of hot, dry weather. To be their healthiest, bigleaf and smooth hydrangeas need more water than do other hydrangea varieties, as their large, soft leaves lose water quickly, becoming tattered-looking during drought, according to the Alabama Cooperative Extension System. Keep hydrangeas mulched to conserve water loss and keep roots cool.
Root Rot Warning
While all hydrangeas like consistent watering, gardeners should avoid overwatering the plants. According to the Alabama Cooperative Extension System, oakleaf hydrangea is particularly vulnerable to root rot when planted in poorly drained soils or after lengthy rains. Fix potential drainage issues at planting time.
Although many hydrangeas prefer some shade, avoid planting them under a large, established tree during the growing season. Large trees require and consume enormous amounts of water in a day, and will draw the moisture away from other nearby plants.
Planting hydrangeas in the fall is preferred, but they can also be planted in spring after the last frost. Avoid planting in temperatures higher than 26.7 degrees Celsius. Choose a site that is away from trees and in a location where hydrangeas will have some shade, as midday sun can scorch hydrangea leaves and damage blooms. Dig a hole that is three times the root ball's width and only as deep as the root ball itself. When backfilling, combine one half of the original soil with an equal amount of organic material. Create a slight mound of soil around the root ball to provide good drainage for roots. Water the plant thoroughly.