I enjoy the althea trees in my yard. Their white flowers with red centers are very pretty through the summer, and they attract bees and hummingbirds. In winter’s Christmas season, after a severe pruning, these trees are attractive with Christmas lights. An artificial deer grazing nearby adds to the effect. Next door, my neighbors have a collection of beautiful flowers and plants, and their althea with striking lavender blooms is my favorite of all. At work, near the dog kennels, there is an unpruned althea perhaps 20 feet tall, with both white and lavender flowers. The two varieties were planted together for a very pretty effect. In summer, wherever I go, an althea is likely to catch my eye.
Althea, Hibiscus syriacus, is native to south-central and south-east China, and spread long ago to India and much of Asia. By the 18th century, it was common in English gardens and in the American colonies. It was collected from gardens in Syria when given its scientific name. Most commonly known as rose of Sharon in North America and rosa de Sharon in Brazil, this name is an allusion to an unknown beautiful flower to which King Solomon compared his bride. In the United Kingdom, it is known as rose mallow or Syrian ketmia, because the plant is in the mallow family. In Italy, for the reason given below, it is known as St. Joseph’s rod.
Joseph, husband to Mary, is often depicted in 
art as holding a rod that is blooming. This appears to be a corruption of a very interesting account of the birth of Christ that was accepted by many early church fathers, the Protoevangelium of James. In this gospel, Mary had been dedicated to the service of God by her parents, and grew up in the temple. When she reached the age of 14, Zacharias the high priest sought God’s guidance in finding her a husband. An angel told Zacharias to assemble all the widowers of the people and have them each bring his rod. When the widowers assembled, the high priest took the men’s rods into the temple and prayed. As the rods were distributed back to the men, a dove came from 
Joseph’s rod, and flew upon his head as a sign. As this story was retold over the years, the story changed. The rod bloomed instead, and became known as the St. Joseph’s rod, Hibiscus syriacus, familiar to us today.
Althea is an upright, branching shrub or small tree. Vase-shaped when young, it can reach a height and width of over 20 feet if left unpruned. Preferring full sun and moist soil, it is highly tolerant of heat, poor soil, and drought. Though not usually a problem, roots may be seen just below the surface. Trunks are gray-white and smooth, with branching beginning near the ground. Branches may be trimmed for tree form. Twigs are thin and gray, with white lenticels.
Branches and twigs branch little unless pruned. They grow into long, straight, upward-reaching stems. On older trees, branches bend outward from the weight of flowers and foliage, and the trees may be as wide as they are tall. Leaves are about 3 inches long, green, and appear alternate on stems. They are broadly ovate, and have 3 distinct lobes with coarsely-toothed margins. Leaf color in autumn, or when the tree is stressed, is yellowish green.
Flowers of the althea bloom in profusion mid-summer through September, and are showy. However, each flower blooms only a day or two before withering and falling off. They may be 3 to 4 inches in diameter, and have 5 petals. Variety colors include solid white, blue, purple, mauve, lavender, and violet. Especially striking are those with a different-colored throat, often red, showcasing the pistil at the center and the stamen around it. Examples of varieties with larger blooms, double blooms, and amazing colors may be found on Pinterest.
Fruit of althea are hairy seeds, that develop in small green capsules about ¾ inches long, having 5 chambers. As the capsules dry, turning brown, 
they split and release the seeds. These seeds are a source of winter food for birds such as goldfinches, titmice, cardinals and wrens. Althea seeds germinate easily. Sprouts can become weedy and form colonies if they are not removed. Some may escape cultivation and naturalize in the wild. Four states have declared althea invasive.
Althea has had, and continues to have, important uses. Many enjoy tea made from its hibiscus leaves and flower petals. Colorful flower petals may be used as a garnish for foods and drinks, and as a delicate wrap in some dishes. They can be made into syrup, jam, and stuffed fritters. As a landscape ornamental, this is a beautiful and hardy hibiscus that inspires names such as mugunghwa, which 
means “eternity” or “inexhaustible abundance” in Korean. Also known as the Korean rose, it is the national flower of South Korea. It appears in the country’s national anthem and on various national emblems of South Korea.
I am undecided as to what is most appropriate to call Hibiscus syriacus trees, when people ask: rose of Sharon, or althea. They are both pretty names, for a popular tree that is both visually pleasing and desirable to make tea and food items. This is an attractive and useful tree to have, call it what you may.