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Hydrangea
Hydrangeas are a genus of more than 70 flowering shrubs, small trees and climbers, mostly from eastern Asia and the Americas, grown for their large flowerheads. Commonly grown members are shrubs such as bigleaf hydrangea (H. macrophylla), and their blooms change colour with soil pH.
Hydrangea ( or ) is a genus of more than 70 species of flowering plants native to Asia and the Americas. Hydrangea is also used as the common name for the genus; some (particularly H. macrophylla) are also often called hortensia. The genus was first described from Virginia in North America, but by far the greatest species diversity is in eastern Asia, notably China, Korea, and Japan. Most are shrubs 1–3 m (3 ft 3 in – 9 ft 10 in) tall, but some are small trees, and others lianas reaching up to 30 m (100 ft) by climbing up trees. They can be either deciduous or evergreen, though the widely cultivated temperate species are all deciduous.
The flowers of many hydrangeas act as natural pH indicators, producing blue flowers when the soil is acidic and pink ones when the soil is alkaline.
Hydrangeas are popular ornamental plants, grown for their large flowerheads, with Hydrangea macrophylla being by far the most widely grown. It has over 600 named cultivars, many selected to have only large sterile flowers in the flowerheads. Hydrangea macrophylla, also known as bigleaf hydrangea, can be broken up into two main categories; mophead hydrangea and lacecap hydrangea. Some are best pruned on an annual basis when the new leaf buds begin to appear. If not pruned regularly, the bush will become very "leggy", growing upwards until the weight of the stems is greater than their strength, at which point the stems will sag down to the ground and possibly break. Other species only flower on "old wood". Thus, new wood resulting from pruning will not produce flowers until the following season.
The following cultivars and species have gained the Royal Horticultural Society's Award of Garden Merit under the synonym Schizophragma:
Hydrangea febrifuga · Hydrangea · Climbing Hydrangea · Wild hydrangea · Rough Leaf Hydrangea · Hydrangea fauriei · Hydrangea glaucescens · Japanese Hydrangea Vine · Bigleaf Hydrangea · Panicled hydrangea · Climbing Hydrangea · Oakleaf hydrangea
Text excerpted from the Wikipedia article Hydrangea by its contributors, under CC BY-SA 4.0; the excerpts and the care summary drawn from them are shared under the same licence.
The care summary was written by AI (Claude, Anthropic) from the sources on this page, with general growing knowledge where they are silent. Check before relying on it.
