The Perennial Question: Do They Return?
The Purple Heart plant (Tradescantia pallida) is a striking ornamental with deep purple, lance-shaped leaves and small, three-petaled pink flowers. It is a favored choice for adding color to garden beds, borders, and containers.
Many gardeners wonder if their Purple Heart plants will return year after year. Tradescantia pallida is a tender perennial, meaning its ability to return depends on the local climate and USDA plant hardiness zone. In warmer regions, typically USDA Zone 7 and above, these plants thrive outdoors year-round, establishing root systems that allow them to regrow each spring.
Conversely, in colder climates, Purple Heart plants may not survive the winter outdoors without protection. Their root system is vulnerable to freezing temperatures, which can prevent them from returning. Gardeners in zones colder than USDA Zone 7 often treat them as annuals, replanting each spring, or take measures to protect them.
Winter Survival Strategies
Purple Heart plants navigate winter differently depending on regional temperatures. In consistently warm climates, such as USDA Zone 9 and higher, these plants often remain evergreen or semi-evergreen. They may experience minor dieback of older foliage but continue slow growth, maintaining a continuous presence.
In borderline climates, typically USDA Zones 6 to 8, Purple Heart foliage often dies back completely to the ground with the first hard frost. However, if the soil does not freeze solid for extended periods, the underground root system can survive. New growth then emerges vigorously from these roots once spring temperatures consistently rise.
In much colder regions, generally USDA Zone 5 and below, the ground often freezes deeply and for prolonged durations. These conditions are too harsh for the roots to endure outdoors. In such environments, Purple Heart plants are cultivated as annuals and do not return. Gardeners wishing to keep them must bring them indoors.
Ensuring Their Return: Overwintering Care
In zones where Purple Heart plants are borderline hardy, gardeners can take steps to encourage their return. In late fall, as temperatures drop, cut back dead or dying foliage to a few inches above the soil line. Then, apply a thick layer of organic mulch, such as straw or wood chips, around the plant’s base. This protective layer, 4 to 6 inches deep, insulates the roots from fluctuating temperatures and potential freezes.
For colder climates where outdoor survival is unlikely, bringing plants indoors is an effective strategy. Before the first hard frost, move potted Purple Heart plants inside to a location with bright, indirect light. Reduce watering significantly during winter, allowing the soil to dry between waterings. This mimics dormancy and prevents root rot.
An alternative for indoor overwintering is to take cuttings from outdoor plants. Healthy stem cuttings, about 4 to 6 inches long, can be rooted in water or moist potting mix. These new plants can then be grown indoors throughout the winter, providing fresh starts for the following spring. Once all danger of frost has passed, both overwintered potted plants and new cuttings can be gradually acclimated and moved back outdoors.