Stewartia

Description

Stewartia is a genus of small to medium-sized trees and shrubs that belong to the tea family, Theaceae. They are native to Asia and the eastern United States. The most commonly cultivated species is the Japanese Stewartia (Stewartia pseudocamellia), which has beautiful, showy white flowers with yellow centers that bloom in early summer. The bark of the tree also adds to its ornamental value, as it peels away in patches to reveal a range of colors, from green to orange-brown.

Taxonomic Information

Appearance

Stewartia trees or shrubs typically grow to be between 15 and 40 feet tall. They have a narrow, pyramidal shape and tend to be multi-stemmed, with a rounded canopy. The leaves are oval-shaped, about 2-4 inches long, and have serrated edges. In the fall, the leaves turn a brilliant red, orange, or yellow. The flowers are large, showy, and white with yellow centers. They bloom in early summer and are cup-shaped, about 2-3 inches in diameter. The bark of the tree is also very striking, as it peels away in patches to reveal a range of colors, from green to orange-brown.

Care Guide

Stewartia trees or shrubs require moderate care and attention. Here are some guidelines for keeping them healthy:

• Water: Water your Stewartia regularly, especially during dry spells. They prefer moist but well-drained soil.
• Fertilization: Fertilize your Stewartia in the spring with a balanced fertilizer. Avoid over-fertilizing, as this can lead to weak growth and susceptibility to pests and diseases.
• Soil: Stewartia prefers well-drained, slightly acidic soil. If your soil is heavy clay, amend it with compost or other organic matter to improve drainage.
• Sunlight: Stewartia prefers partial shade to full sun. Too much shade can lead to weak growth and poor flowering.
• Hardiness Zones: Stewartia is hardy in USDA zones 5-8.

Common Pests & Diseases

Stewartia is generally resistant to pests and diseases, but it can occasionally be affected by the following:

• Leaf spot: This fungal disease can cause yellow or brown spots on the leaves. It can be prevented by avoiding overhead watering and improving air circulation.
• Aphids: These small insects can suck the sap from the leaves and flowers, causing stunted growth and distorted flowers. They can be controlled with insecticidal soap or neem oil.
• Mites: These tiny insects can cause leaves to turn yellow or brown and drop prematurely. They can be controlled with insecticidal soap or neem oil.

Habitat

Stewartia is native to Asia and the eastern United States. It prefers moist, well-drained soil and partial shade to full sun. It can be found in woodlands, along streams and rivers, and in other moist areas.

Question and Answer

Q: Can Stewartia be grown in containers?

A: Yes, Stewartia can be grown in containers, but it may not reach its full size and flowering potential.

Q: How often should I water my Stewartia?

A: Water your Stewartia regularly, especially during dry spells. They prefer moist but well-drained soil.

Q: Can Stewartia tolerate full sun?

A: Yes, Stewartia can tolerate full sun, but it prefers partial shade.

Q: How can I control leaf spot on my Stewartia?

A: Leaf spot can be prevented by avoiding overhead watering and improving air circulation. If your Stewartia is already infected, you can remove and destroy the affected leaves and treat with a fungicide.

Related Plants

• Franklinia alatamaha
• Gordonia lasianthus
• Thea sinensis
• Camellia japonica

References

• “Stewartia pseudocamellia.” Missouri Botanical Garden. Accessed 19 August 2021. <https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=c235>
• “Stewartia.” Plant of the Week. University of Arkansas Division of Agriculture Research and Extension. Accessed 19 August 2021. <https://www.uaex.edu/yard-garden/resource-library/plant-week/stewartia-6-17-11.aspx>
• “Stewartia.” NC State Extension. Accessed 19 August 2021. <https://content.ces.ncsu.edu/stewartia>