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Why are rhododendrons and azaleas important in horticulture?

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Cluster of blooming pink azaleas, Rhododendron roseum, with green leaves and dark foliage in the background. — Ericales Flowering rhododendron.

Rhododendrons and azaleas, which belong to the Ericales order and the Ericaceae family, are highly valued in horticulture primarily for their ornamental qualities.12

These plants are widely cultivated for their showy, diverse, and often fragrant flowers, which appear in a broad spectrum of colors including white, yellow, pink, scarlet, purple, and blue. In addition to their blooms, they are prized for their handsome foliage, which ranges from thick, leathery evergreen leaves to deciduous varieties.12

Gardeners and horticulturists have bred hundreds of horticultural forms from species native to regions such as Asia and North America. Their versatility in size—ranging from low-growing, matlike dwarf species to tall trees—allows them to be used in various landscape settings. While many are celebrated for their aesthetic contribution to gardens, some species, such as the common rhododendron (R. ponticum), have become invasive species in certain regions, highlighting the importance of responsible horticultural selection.12