Japanese pagoda tree (Styphnolobium japonicum)
The Japanese pagoda tree (Styphnolobium japonicum) offers fragrant summer blooms and robust tolerance for urban settings. A low-maintenance specimen for large landscapes.
Complete Plant Information
Overview
The Styphnolobium japonicum, commonly known as the Japanese pagoda tree, is a magnificent and durable specimen celebrated for its tolerance of difficult urban environments. This medium to large deciduous tree provides significant shade with its broad, rounded crown, maturing between 50 and 75 feet tall, though sometimes reaching greater heights. Its structure is enhanced by attractive, lustrous, dark green compound foliage that remains attractive well into the fall season.
A significant landscape asset of Styphnolobium japonicum is its fragrant bloom display occurring late in the summer, a time when many other deciduous trees have finished flowering. The creamy white, pea-like flowers appear in large terminal panicles, eventually dropping to create a striking white covering beneath the canopy. Due to its hardiness and moderate maintenance needs, the Japanese pagoda tree is an outstanding choice for large-scale plantings requiring longevity and visual impact.
Fast Facts
- Plant Family: Fabaceae
- Plant Type: Tree
- Native Range: China, Korea
- Hardiness Zones: USDA Zones 4-8
- Size at Maturity:
- Height: 50-75 ft
- Spread: 50-75 ft
- Bloom Time: July to August
- Bloom Description: Creamy white
- Sun Exposure: Full sun to part shade
- Water Needs: Medium
- Maintenance Level: Low
How to Grow
The best time for planting your Styphnolobium japonicum is typically during the dormant season, ensuring roots establish before summer heat arrives. Site selection is key; this tree thrives best in rich, medium-moisture, well-drained sandy loams. While it accepts part shade, it performs optimally when situated in full sun, which encourages robust flowering.
Established trees demonstrate notable resilience; Styphnolobium japonicum exhibits tolerance to regional heat and periods of drought. Newly planted saplings require consistent monitoring and deep watering until their root systems are fully developed, which can take several years. Fertilization is rarely necessary if soil conditions are adequate, keeping maintenance low.
Pruning should focus primarily on removing dead or crossing branches, especially when the tree is young, to establish a strong central leader. Be aware that saplings of the Japanese pagoda tree might take up to ten years before they begin producing their signature late-summer flowers.
Landscape Uses
The sheer size and durability of Styphnolobium japonicum make it an exceptional choice for large-scale functional planting. It excels as a definitive Shade Tree, providing vast canopies over lawns or expansive properties where future size is accounted for. Its established tolerance for pollutants also qualifies it perfectly for use as a Street Tree in urban environments where resilience is paramount.
When designing around this impressive specimen, consider complementing its large scale with lower-growing shrubs that appreciate its filtered afternoon shade, such as certain hostas or astilbes in a mixed border. Because the falling flowers can present a clean-up concern on walkways, consider massing the Japanese pagoda tree in turf areas or park settings rather than immediately adjacent to paved patios. Utilizing several plants together can create an impressive all-star screen or grand avenue planting.
Standout Features
Flower Qualities
- Showy
Fruit Qualities
- Showy
Noteworthy Characteristics
Styphnolobium japonicum, commonly called Japanese pagoda tree or Chinese scholar tree, is native to China and Korea, but not Japan. It is a medium to large deciduous tree that typically matures to 50-75’ (less frequently to 100’) tall with a broad rounded crown. It is generally cultivated for its attractive compound foliage and fragrant late summer flowers. Pinnate leaves (to 10” long), each with 7-17 oval, lustrous, dark green leaflets, remain attractive throughout the growing season. Flowers give way to slender, 1- to 6-seeded, knobby, bean-like pods that mature to brown in fall and persist into winter.
Tolerances
- Drought
- Air Pollution
Potential Problems
The Japanese pagoda tree generally enjoys a reputation for being free of serious insect or disease issues, minimizing overall maintenance. However, gardeners should remain vigilant for certain fungal concerns that can affect the plant occasionally. These include twig blight, canker, powdery mildew, and rust, all of which typically thrive in humid conditions or where air circulation is poor. Verticillium wilt is another potential concern requiring careful site observation. Watch actively for leaf hoppers, which may occasionally appear on the foliage during peak growing season.
Frequently Asked Questions
What hardiness zones is Japanese pagoda tree suitable for?
The Styphnolobium japonicum is reliably hardy across USDA Zones 4 through 8.
How large does Styphnolobium japonicum grow?
This species typically reaches a mature height between 50 and 75 feet, often with an equally wide spread of 50 to 75 feet, creating a very substantial canopy.
What sun exposure does Japanese pagoda tree need?
While it can tolerate partial shade, this tree develops best and flowers most prolifically when situated in full sun.
When does Styphnolobium japonicum bloom?
The fragrant flowers usually appear late in the season, blooming from July through August, boasting a creamy white color.
Conclusion
The Japanese pagoda tree stands out as a supremely durable and aesthetically pleasing choice, delivering fragrant summer flowers and robustness against urban stressors like air pollution. Its low maintenance requirement and imposing stature confirm Styphnolobium japonicum’s value in large landscape plans. Before planting, ensure your location falls within USDA Zones 4-8 and that you have adequate space for its mature 75-foot spread.
Companion Planting
Choosing companions for the Styphnolobium japonicum involves selecting plants that can handle the deep shade cast by its mature canopy or thrive in the sunnier conditions it prefers when young. Underneath the tree, consider planting shade-tolerant groundcovers like Vinca minor or pachysandra to suppress weeds beneath the large drip line. For foundation plantings near the edge of the canopy, flowering shrubs that benefit from afternoon shade, such as rhododendrons or azaleas, offer vibrant color contrast against the tree’s dark green foliage.
Wildlife Benefits
While not a primary nectar source for early pollinators, the late blooming period of the Japanese pagoda tree provides essential forage when other sources diminish in mid to late summer. The large clusters of creamy white flowers are attractive to various late-season bees and other beneficial insects seeking sustenance. Furthermore, the resulting bean-like seed pods, while not always heavily consumed, offer persistent texture and visual interest into the winter months, which can sometimes benefit winter birds looking for residual food sources.
