Ginkgo biloba ‘Princeton Sentry’ (Maidenhair Tree)

Ginkgo biloba ‘Princeton Sentry’ is a remarkable cultivar of the ancient and revered Ginkgo biloba tree, known for its unique characteristics and adaptability. This columnar selection stands out for its upright, narrow form, making it an ideal choice for urban landscapes and tight spaces where a traditional Ginkgo’s broad growth would be impractical.

Ginkgo biloba ‘Princeton Sentry’: An In-depth Look

‘Princeton Sentry’ is a male cultivar of Ginkgo biloba, celebrated for its vigorous, columnar habit. It lacks the messy fruits produced by female trees, offering a cleaner alternative for urban settings. This cultivar is distinguished by its dense branching and symmetrical, pyramidal shape. It is commonly known as the maidenhair tree due to the resemblance of its leaves to the pinnae of the maidenhair fern (Adiantum genus).

Native: Originally from China, Ginkgo biloba is the last surviving member of a group of ancient plants believed to have inhabited the earth up to 270 million years ago.

Plant Type and Habit: This tree is a slow-growing, columnar, deciduous conifer, though it does not bear cones. Ginkgo biloba is known for its longevity, with some specimens living over a thousand years.

Size: ‘Princeton Sentry’ reaches about 40-50 feet in height (12-15 meters) with a notably slender spread of 20-30 feet (6-9 meters) at maturity, making it significantly more columnar than the species.

Flowers: As a male cultivar, ‘Princeton Sentry’ produces small, yellow-green catkins in the spring. These flowers are not particularly showy but contribute to the tree’s overall appeal when they emerge.

Fruits: Being a male cultivar, ‘Princeton Sentry’ does not produce fruits or the notorious smelly seeds associated with female Ginkgo trees, making it a tidy choice for public and residential areas.

Foliage: Its leaves are the classic fan shape associated with Ginkgo biloba, turning a brilliant yellow in the fall. This foliage provides stunning visual interest and makes ‘Princeton Sentry’ a valuable addition to any landscape.

Bark: The bark of Ginkgo biloba is light gray, deeply furrowed, and provides significant winter interest with its rugged texture.

Hardiness: Ginkgo is exceptionally hardy, tolerating zones 3-9.

Award: Recipient of the prestigious Award of Garden Merit of the Royal Horticultural Society.

Uses: Due to its upright growth and resistance to pests and diseases, ‘Princeton Sentry’ is an excellent choice for urban street trees, avenues, and small gardens. Its tolerance for pollution and compacted soils also makes it a resilient option for challenging urban environments.

Wildlife: Ginkgo biloba does not significantly attract wildlife due to its lack of nectar-rich flowers or fleshy fruits.

Deer and Rabbits: Ginkgo biloba is highly resistant to damage from deer, making it an excellent choice for areas where these animals are prevalent.

Drought / Salt Tolerance: Once established, Ginkgo biloba is highly drought-tolerant, requiring minimal irrigation. It is also salt, heat, and pollution tolerant.

Toxicity: This Ginkgo biloba cultivar is not toxic to humans and pets.

Invasiveness: Ginkgo biloba is not considered invasive. Its slow growth rate and specific reproductive biology limit its spread.

How to Grow and Care for a Ginkgo Tree

Sunlight: Ginkgo biloba prefers full sun but can tolerate partial shade. Full sun encourages the best fall color.

Soil: Ginkgo is adaptable to a wide range of soil types but prefers well-drained soils. It can grow in acidic, neutral, or alkaline pH levels.

Water: Water young trees regularly until established. Mature trees are drought-tolerant but benefit from occasional deep watering during extended dry periods.

Fertilization: Ginkgo trees generally do not require much fertilization. If growth seems slow, apply a balanced fertilizer in early spring.

Pruning: Prune during dormancy in late winter or early spring. Remove any dead, damaged, or diseased branches and thin out dense areas to improve air circulation.

Mulching: Apply a 2-3 inch layer of organic mulch around the tree’s base, extending out to the drip line but not touching the trunk. Mulch helps retain soil moisture, regulates soil temperature, and suppresses weeds.

Propagation: Propagate by semi-hardwood cuttings.

Pests and Diseases: Ginkgo biloba trees are remarkably resilient and have few significant problems regarding pests and diseases.