Description: Althea is a multi-stemmed shrub that typically grows upright with a vase-shaped or rounded habit. It features attractive green foliage that may turn yellow in fall before dropping. The most notable feature of Althea is its large, showy flowers, which resemble hibiscus blooms. These flowers come in a variety of colors, including white, pink, purple, and blue, often with a contrasting throat. They bloom profusely from mid- to late summer and continue into fall, attracting bees, butterflies, and hummingbirds.
Size: The size of Althea can vary depending on the cultivar and growing conditions. On average, it typically reaches a height of 8 to 12 feet (2.4 to 3.7 meters) and a spread of 6 to 10 feet (1.8 to 3 meters). However, some varieties may grow taller or wider. Althea can be pruned to maintain a smaller size or trained into a small tree with a single trunk.
Best Growing Zones: Althea is adaptable to a wide range of climates and soil types, making it suitable for USDA hardiness zones 5 to 9. It thrives in regions with hot summers and cold winters but can also tolerate milder climates. It prefers full sun to partial shade and well-drained soil but can tolerate a variety of soil conditions, including clay and sandy soil.
Soil Requirements: While Althea prefers well-drained soil, it can tolerate a variety of soil types, including clay, loam, and sandy soil. It is relatively drought-tolerant once established but benefits from regular watering during dry periods, especially in hot weather. Adding organic matter, such as compost, to the soil can improve its fertility and drainage.
Maintenance: Althea is generally low-maintenance but may benefit from occasional pruning to control its size and shape, remove dead or damaged branches, and promote flowering. Pruning is best done in late winter or early spring before new growth begins. Applying a balanced fertilizer in spring can help encourage healthy growth and flowering.
