Antique hydrangeas are old-fashioned blooming shrubs that have been around for centuries. They produce ball-shaped clusters of small, four-petaled flowers in several colors, including blue, green, white, and pink. These flowers are often used in wedding bouquets and last for years in dried flower arrangements. The best selling hydrangeas are known as mop heads and belong to the Hydrangea macrophylla genus. These beautiful plants are the most common hydrangeas grown as of 2011.
The pink and blue varieties have flowers that can change color depending on the type of soil in which they are grown. Soil that has a high aluminum content will produce the highly desirable baby blue flowers, while low amounts of aluminum usually result in pale to bright pink flowers. White and green antique hydrangeas do not change color. Antique hydrangeas usually grow to a maximum of 4 to 7 feet (1.2 to 2.1 m) tall and have large, light green leaves. Flowers usually appear from mid-summer to early fall.
Hydrangeas do not require much care, needing only rich soil and plenty of water. It is very important to plant antique hydrangeas where they will be provided with morning sunlight and some shade in the afternoon. Plants in northern areas should be given more direct sunlight than those in southern climates. Hydrangeas do not do well in very hot weather and should be given more shade in areas where the summers are hot and dry.
Most hydrangeas are fairly tolerant of cold weather, but they will not survive a deep freeze. They should be protected from ice and damaging wind with a thick layer of mulch. Lightweight materials such as straw or dried leaves work best, as they allow some air to circulate, but will not damage the delicate branches. They also make good potted plants and can be brought indoors for the winter.
Antique hydrangeas should be pruned with restraint, and need not be pruned at all in most cases. Only dead stems or flowers should be removed as more severe pruning will prevent the plant from blooming. Flower buds form on old wood, so any pruning that is done in fall, winter, or spring will result in few flowers the following summer.
New antique hydrangea plants can be started from cuttings. A branch that did not produce any flowers is said to be the best for propagating. The lower leaves should be removed and the remaining ones should be cut down to about half of their original size. The stem can be dipped into a root hormone powder to speed up root growth, and then planted in coarse sand or vermiculite and covered with plastic wrap until rooted. Most cuttings will root within two to three weeks.