Spiderwort Tradescantia

The spiderworts comprise a genus of perennial plants that may have a sprawling or erect habit and belong to the spiderwort family (Commelinaceae). There are 86 accepted species, and they are native from southern Canada to South America and have become naturalized throughout the world. Generally, they are weakly upright plants that grow in clumps in woodland areas and open fields. They can form a dense ground cover and in some areas are regarded as invasive weeds. The genus name, Tradescantia, is in honor of John Tradescant who was a plant collector and gardener for King Charles I of England. He and his son introduced these plants to Europe. Spiderwort gets its name from the thick, sticky secretion that is present when a stem is cut.  This substance becomes thread-like and silky when it hardens, appearing similar to a spider web.

These plants prefer bright, indirect light and moist, well-drained, acidic, humus soil or potting mix. They can tolerate full sun but need protection from the afternoon sun. Too much sun may cause leaf scorch. Water these plants when the top inch of the soil is dry. The hardy types can be grown in USDA Hardiness Zones 4–9, but the tropical and semi-tropical species are hardy from zones 9 to 12. The tropical and semi-tropical plants prefer temperatures of 60 to 80 degrees Fahrenheit. Outdoor plants of this type need to be brought indoors before temperatures drop below 50 degrees. Pinching back the stems will encourage new growth and prevent leggy stems. These plants are easy to propagate from stem cuttings, leaf cuttings, and division, and they root easily at the stem nodes.

The stems and leaves of most of the species are somewhat succulent. The leaves are fleshy, mucilage-filled, and the leaf color ranges from purple, green, or variegated. The flowers are small, delicate, 3-petaled, saucer-shaped, and are found in shades of white, pink, purple, or blue. The blooms are short-lived, but the flowering season lasts 4 to 6 weeks. The fruit is a tiny, 3-valved capsule that splits open to release 2 or more seeds.

Spiderworts are widely available and are frequently used as ornamentals or houseplants. This plant also work well mass planted along a slope, walkway or patio garden. Its attractive foliage makes it a striking accent plant or a feature in a native or cottage garden. They may be used in perennial beds of native and pollinator gardens. Tropical forms can be used as houseplants and in hanging containers but should be avoided in the landscape as they can become quite weedy. As a houseplant, they provide delicate flowers and colorful, cascading foliage. They are easy to care for and fast-growing.

Insects, Diseases, and Other Plant Problems: Monitor for spider mites, aphids, thrips, and mealybugs. Snails and caterpillars can damage young shoots. Too much direct sun can cause leaf scorch. Soggy and poorly drained soils can cause root rot. In cool and humid conditions, botrytis blight can occur causing a gray mold to grow on the leaves and flowers. Some species can be invasive. Choose the best variety for your climate and be aware of any invasive potential if used as a mass planting.

The leaves and sap of some species of Tradescantia can cause skin irritation or rash in people and pets. Ingestion can cause mouth or stomach irritation.