Evergreen groundcovers keep life in the landscape even in winter. Gaultheria, or wintergreen, is a sweet little plant with mint scented leaves and edible berries. It is perfect for cooler regions and is native to North America. Some tips below can help you decide if it is right for your garden as well as a guide on how to care for wintergreen.
I. Appearance and Characteristics
Gaultheria procumbens, also called the eastern teaberry, the checkerberry, the boxberry, or the American wintergreen, is a species of Gaultheria native to northeastern North America from Newfoundland west to southeastern Manitoba, and south to Alabama. It is a member of the Ericaceae (heath family).
G. procumbens is a small, low-growing shrub, typically reaching 10–15 cm (4–6 in) tall. The leaves are evergreen, elliptic to ovate, 2–5 cm (3⁄4–2 in) long and 1–2 cm (1⁄2–3⁄4 in) broad, with a distinct oil of wintergreen scent.
The flowers are pendulous, with a white, sometimes pink-tinged, bell-shaped corolla with five teeth at the tip 8–10 mm (0.31–0.39 in) long, and above it a white calyx. They are borne in leaf axils, usually one to three per stem. The anthers are forked somewhat like a snake’s tongue, with two awns at the tip.
The fruit is red and 6–9 mm (0.24–0.35 in) across. It is an epigynous berry, with the majority of the flesh of the fruit being composed of the fleshy calyx.
The plant is a calcifuge, favoring acidic soil, in pine or hardwood forests, although it generally produces fruit only in sunnier areas. It often grows as part of the heath complex in an oak–heath forest.
G. procumbens spreads by means of long rhizomes, which are within the top 2–3 cm (3⁄4–1+1⁄4 in) of soil. Because of the shallow nature of the rhizomes, it does not survive most forest fires, but a brief or mild fire may leave rhizomes intact, from which the plant can regrow even if the above-ground shrub was consumed.
This plant has gained the Royal Horticultural Society’s Award of Garden Merit.
II. How to Grow and Care
Sunlight
In their native habitat, wintergreen plants grow in the dappled shade of temperate forests, where they creep along and form dense colonies among other acid-loving plants like mountain laurels and rhododendrons. The plants are shade-tolerant and may even grow in dense shade but will produce few or no flowers. Bright filtered sunlight will keep plants from scorching while giving them enough energy to produce blossoms and fruit.
Temperature and Humidity
Areas with mild summer temperatures and average to high humidity, as found in the Northeastern United States, are favorable to growing wintergreen. The plants fare poorly in the hot, dry climate of the Southwest.
Watering
Consistent moisture is important to the health of wintergreen. The more sunlight your plants receive, the more moisture they will require. In dry spells and droughts, give them one inch of water per week.
Soil
Wintergreen is not finicky about soil quality, it will also grow in nutrient-rich soil as well as in poor soil as long as it is well-drained. As a member of the heath (Ericaceae) family, wintergreen needs acidic soil between 4.5 and 6.0 for optimum plant health1. Perform a soil test to check the acidity of your soil, and if the pH is higher than 6.5, you must lower it with acid-rich amendments such as peat moss, which also helps with drainage issues.
Fertilizing
No supplemental fertilizer is necessary for wintergreen plants. These native plants are adapted to grow in areas with poor soil that is low in nutrients. As an understory plant, they get sufficient nutrients from the decaying leaves of deciduous trees, which you can mimic by spreading a layer of leaf mold around the base of the plants.
Pruning
In the spring, prune back the old, woody stems to encourage new growth.
Propagation
Most wintergreen cultivars are protected by plant patents or trademarks and may not be propagated in any form. Therefore, propagation is limited to the species only.
Wintergreen plants spread by creeping rhizomes and, as such, are easy to propagate with rooted stems. This method is preferable over propagation from seed, which in addition to being much lengthier has the added challenge of the seeds being tiny and requiring up to 10 weeks of cold stratification.
Here’s how to propagate wintergreen from a rooted stem:
Select a strong, healthy stem that creeps across the ground.
Carefully dig up the stem with all its roots attached.
If there are only a few roots present, dust the bottom with rooting hormone (optional)
Plant the stem in a 4-inch pot filled with damp potting mix. Make sure the roots are fully covered with soil.
Place the pot in an outdoor location away from direct sunlight and keep it evenly moist.
When new growth appears and the stem does not wiggle when you gently tug on it, it has rooted. Wait a few more weeks to let it grow some more, then replant it in the landscape or in a larger pot.
Potting and Repotting
Wintergreen is suitable to be grown in pots. Select a pot with large drainage holes and use a potting mix with a good amount of peat and sand, which will mimic the drainage and acidity the plants need. Alternatively, use a specially formulated planting soil for acid-loving plants. Keep in mind that potted plants need more frequent watering than plants in the landscape, especially in hot summer weather.
When you see roots coming from the drainage hole of the container, it’s time to repot the plant to a larger container with fresh soil.
Overwintering
Wintergreen is a very winter-hardy perennial that needs no winter protection. However, if you grow it in pots, the roots are not sufficiently insulated against the cold. Burying the pots in the ground, or creating a planting silo are two of the methods to winterize potted plants.
Pests and Diseases
The volatile oils of wintergreen deter most insects and the plant is blissfully free of serious pests or diseases. Occasionally, aphids and thrips may seek out the plants. They are easy enough to blast away with a jet of water.
Poorly draining soils can lead to root rot or mildew. Other potential diseases are black and mildew and leaf spot.
III. Uses and Benefits
- Culinary uses
The fruits of G. procumbens, considered its actual “teaberries”, are edible, with a taste of mildly sweet wintergreen similar to the flavors of the Mentha varieties M. piperita (peppermint) and M. spicata (spearmint) even though G. procumbens is not a true mint. The leaves and branches make a fine herbal tea, through normal drying and infusion process. For the leaves to yield significant amounts of their essential oil, they need to be fermented for at least three days. The berries and leaves contain methyl salicylate, a compound that is closely related to aspirin.
Teaberry extract can be used to flavor tea, candy, medicine and chewing gum. Teaberry is also a flavor of ice cream in regions where the plant grows. It likewise inspired the name of Clark’s Teaberry chewing gum.
- Wildlife value
Wintergreen is not taken in large quantities by any species of wildlife, but the regularity of its use enhances its importance. Its fruit persists through the winter, and it is one of the few sources of green leaves in winter. White-tailed deer browse wintergreen throughout its range, and in some localities it is an important winter food. Other animals that eat wintergreen are wild turkey, sharp-tailed grouse, northern bobwhite, ring-necked pheasant, black bear, white-footed mouse, and red fox. Wintergreen is a favorite food of the eastern chipmunk, and the leaves are a minor winter food of the gray squirrel in Virginia.
- Traditional use
The plant has been used by various tribes of Native Americans for medicinal purposes. The Delaware, Mohicans, and several other tribes made tea from wintergreen leaves to treat kidney disorders. The Great Lakes and Eastern Woodlands tribes used a wintergreen poultice as a topical treatment for arthritic pain.
