Backyard Gardening

By Kathryn Dorman

I have a plant, Tradescantia zebrina, that is nearly impossible to kill if it is grown inside as a houseplant. This plant is now commonly called the inch plant but was formerly called the Wandering Jew. Even small pieces of this plant will easily sprout roots and can grow into a whole new plant. When I started writing this article, I thought of the song, “They Call Me the Wanderer,” performed by Dion (Dimucci). The reproductive capability for T. zebrina is such that it really does roam around, and around, and around.’  In fact, if grown in a tropical or subtropical climate (Cold Hardiness Zone 9 or higher), it doesn’t take much for this plant to spread and become invasive. 

According to the Centre for Agriculture and Bioscience International (CABI), in 2005, T. zebrina was declared an invasive plant on Gros Piton, a volcanic mountain and World Heritage Site in Saint Lucia, West Indies. T. zebrina was deliberately planted, and in about seven years, it spread several hundred meters along the trail. In Hawaii, this wandering plant is now naturalized, and covers large areas of ground in secondary forest (https://www.cabidigitallibrary.org/doi/10.1079/cabicompendium.110354)).”

However, those of us living in Pennsylvania need not panic. There will not be an invasion of this plant into our forest habitats. Once a killing frost occurs in the fall, any T. zebrina growing outside will be dead. It will not survive freezing temperatures.  

The inch plant, native to tropical regions of Mexico, is a succulent member of the Commelinaceae, or spiderwort, family. It is an herbaceous perennial with simple, alternate leaves. The silver and green-striped leaves of T. zebrina sprout from the plant’s main stem about every inch, which explains its updated common name (See Photo 1). The undersides of the leaves are purple, or sometimes purple and green striped. According to the University of Florida Extension (UFE), small, pink, tri-lobed flowers can occur on the inch plant at any time of the year (https://edis.ifas.ufl.edu/publication/FP620). I have never seen my inch plant in bloom, but the flowers are similar to those of other Tradescantia species, such as the spiderwort (T. virginiana).

The inch plant will grow in various well-drained soils and should be grown in partial to deep shade, out of direct sunlight (UFE). If it doesn’t, the inch plant can become leggy, and the leaves will lose their luster. Water thoroughly but allow the soil to partially dry out before watering again. As with many houseplants, root and stem rot can occur in soggy soil. Cut back on watering during winter, which is the plant’s resting period. Fertilize twice a month only in spring and summer. 

Pinch back the stems to keep this trailing plant contained, and to encourage bushier foliage.  Plants can be cut back every spring and can be taken outside to a shady location for the summer. You can use any of the cuttings to grow new plants (See Photo 2). 

There are no serious pest or disease problems for the inch plant (UFE). Monitor the inch plant for aphids and spider mites. To get rid of them, pinch off the infected stems and spray the plant with water. 

Contact with the foliage or plant sap may cause skin irritation in some individuals. Be cautious about letting dogs or cats have access to any Tradescantia species. If ingested, these plants may cause vomiting or worse. Keep the plants up where pets cannot reach or climb. Be diligent about picking up fallen leaves and broken stems.

A couple of years ago, I let a bunch of cuttings sit in water over an entire winter. In the spring, I took the cuttings outside to the compost bin so I could trim out the bad parts. I planted the better-looking stems together in a tall pot that sat on the deck all summer. At some point, I noticed that the bad parts had taken root in the compost bin! Last year, I planted several different kinds of plants together in two large pots. Halfway through the summer, I realized I had dropped an inch plant stem on the ground below the planters. That little piece took root and was still growing until the first killing frost.

The inch plant can be used in tall containers and in hanging planters. Since I am partial to purple, I like the inch plant. I get my color choice without having to deal with a lot of heavily scented flowers, which can aggravate my pollen and fragrance allergies. The inch plant is easy on the eyes and easy to maintain.

  

Kathryn Dorman has been a Penn State Extension certified Master Gardener of Clinton County since 2017. She can be reached at clintonmg@psu.edu, or through the Clinton County Master Gardener Hotline at (570) 858-0198.