Hydrangea macrophylla: Of the various types of hydrangeas, this is the most well known. This group is also known as the big leaf hydrangea and has flowers of one of two forms, mophead or lace cap. The mopheads are ball-shaped and the lacecaps are plate-like. These varieties tend to be the hardiest in wind and will accept sun or shade provided there is enough moisture. Because of their large leaves and flower heads, these plants require a large amount of water, and have even been known to tolerate moist conditions. The flowers on these plants range from white to pink to blue. Flower color is usually depen- dent on soil acidity. They tend to mature to around 4 feet. Prune in winter lightly overall but be sure to retain as many of the fat flower buds as possible. Protect early emerging flower buds from frost. Zones 5 & 6.
Eg. Endless Summer—mophead Lady in Red—lacecap
Hydrangea serrata: This group has leaves with a serrated edge like a knife. They are very similar in their growth and habit to Hydrangea macrophylla, but are not as tolerant to adverse conditions. This group prefers a shady to morning sun location out of the wind. They tend to mature to around 3 feet. Pruning is the same as for the macrophylla group. Zones 5 & 6.
Eg. Blue Bird—lacecap
Hydrangea arborescens: A very hardy native that is tolerant of drought once established. Some protection from wind is beneficial, as the white blossoms are so large that they may be damaged. Tends to mature between 4 and 5 feet. Can be pruned to the ground for winter. Zone 3.
Hydrangea paniculata: Tolerates extreme cold but not wind. The large white-to-pink blossoms on these plants can be easily broken in high winds. These are large plants, maturing up to 15 feet. Selec- tive winter pruning can increase the bloom size for these plants.
Hydrangea quercifolia: Also known as the oak leaf hydrangea. Large leaves achieve their best fall color when planted in full sun. These plants are not tolerant of high winds, so choose a protected site. Tend to mature around 5 feet. Prune in winter. Zones 5 & 6.
Hydrangea anomala subsp. Petiolaris: Also known as climbing hydrangea. This vining member of the hydrangea family has a lacecap-type flower. It grows as tall as it is allowed (supported by clinging roots), and then flowers at the top of the vine. Prun- ing is not usually necessary. Zone 4.
Schizophragma hydrangeoides: A relative to hydrangeas known as the Japanese Hydrangea, it is also a climber. These flower best in full sun with a lacecap-type flower. Pruning is not usually necessary. Zone 5.