Princeton Sentry ginkgo

Sun

Full sun; tolerates light shade, but develops a better crown and autumn colour in an open, sunny position.

Water

Water regularly while establishing. Established trees tolerate moderate drought, but benefit from deep watering during prolonged dry weather.

Soil

Deep, well-drained soil; tolerates clay, loam, sand and a broad pH range. Avoid persistently waterlogged ground.

Height

40-60 ft (12-18 m), potentially taller with age

Spread

15-25 ft (4.5-7.5 m), gradually broadening with age

Foliage

Green, fan-shaped leaves with radiating veins and often a central notch. Leaves turn golden yellow in autumn and may fall almost together after a hard frost.

Growth

Slow to moderate; often slow for the first few years after planting.

Care needed

Low

• Deer resistant
• Drought tolerant
• Cold hardy
• Disease resistant
• Wildlife

Northern hemisphere months. In Australia, shift them by six.

Difficulty

Easy

Toughness

Very tough

Pick your zone, country, light and whether you have pets.

1. Planting day

   7 ft (2 m)

2. After 1 year

   8 ft (2.5 m)

3. After 2 years

   10 ft (3 m)

4. After 3 years

   11 ft (3.5 m)

5. After 5 years

   15 ft (4.5 m)

About 26 years to full size.

From a typical nursery size, at an average rate for this kind of plant. A rule of thumb, not a forecast.

Cats and dogs

Safe

Growth rate

Slow

• Plant with the root flare at ground level, leaving ample room for the mature crown and roots.
• Water deeply during dry spells for the first two or three growing seasons; let the surface soil begin to dry between waterings.
• Spread 2-3 in (5-8 cm) of organic mulch over the root zone, keeping it clear of the trunk.
• Feed only if growth is poor and a soil test indicates a deficiency; routine feeding is usually unnecessary.
• Stake only if the root ball moves in the wind, and remove supports once the tree is stable, usually after one growing season.
• Remove shoots arising below the graft union so they do not replace the named cultivar.

Pruning. Prune lightly in late winter while dormant, removing dead, damaged or crossing branches and retaining one main leader. Correct competing leaders while the tree is young; avoid topping or routinely shortening the crown.

Autumn

Plant in workable, well-drained ground where winters are mild; in very cold regions, wait until spring.

Late winter

Inspect the branch structure and remove damaged branches or competing leaders.

Spring

Plant in colder regions, renew mulch and check that ties are not rubbing or tightening.

Summer

Water young trees deeply during dry weather and check soil moisture beneath the mulch.

Early autumn

Remove unnecessary stakes and any shoots growing from below the graft.

Late autumn

Collect fallen leaves for leaf mould or compost, and keep wet leaves off paths.

• Use as a narrow specimen beside a lawn or terrace, allowing for its eventual height and spread.
• Plant in a repeated avenue along a broad drive or boundary for a strong upright rhythm.
• Set against dark evergreens to make the yellow autumn foliage stand out.
• Combine with low ornamental grasses and perennials for a simple, open planting beneath the crown.

Garden styles it suits: Architectural minimal, Modern, Urban city garden, Formal, Japanese and Autumn colour.

Plant it with: Japanese forest grass, Lilyturf, Autumn moor grass, Christmas fern, Hellebores and Daffodils.

Wildlife: The crown provides perching and nesting space for birds, but ginkgo supports relatively few leaf-feeding insects outside its native range. This male cultivar offers no fleshy seeds and is not a useful nectar plant.

• Poor establishment or scorched leaf edges: check moisture around the original root ball and water deeply; avoid frequent, shallow sprinkling.
• Yellowing foliage and dieback in wet ground: improve drainage or move a young tree to a better-drained site rather than adding more water.
• Competing leaders or weak branch attachments: select one main leader and make small corrective cuts while the tree is young.
• Occasional scale insects: inspect twigs for attached bumps and sticky deposits; tolerate light infestations or use a locally approved horticultural oil according to its label.

This male cultivar normally produces no seeds. Its foliage is not known to be a significant poisoning hazard to cats, dogs or horses, but do not offer it as feed. On female ginkgos, the fleshy seed covering can irritate skin, and the kernels can cause serious poisoning, including seizures, in people and animals if eaten; cooking does not make unrestricted consumption safe. Concentrated ginkgo leaf products can also interact with medicines.

• Seed-grown ginkgo (Ginkgo biloba)

  The leaves look much the same, but ordinary seedlings usually develop a broader, less uniform crown and may be female. A nursery label and reliable propagation history are the best confirmation of 'Princeton Sentry'.

• Maidenhair fern (Adiantum spp.)

  Its small, fan-shaped leaflets resemble ginkgo leaves, but they grow along slender fern fronds rather than on the woody branches of a tree.

The species name biloba means 'two-lobed', referring to the often-notched leaves, while the common name maidenhair tree refers to their resemblance to maidenhair fern leaflets.

Propagation. Usually propagated commercially by grafting or budding onto seed-grown ginkgo rootstock. Cuttings can be difficult to root; seed will not reproduce 'Princeton Sentry' and may produce female trees.

Accepted botanical name

Ginkgo biloba

In the US and Canada

Introduced in the lower 48 states.

Native range

China Southeast.

Measured

Soil pH 5.2 to 7.5. Average height 3000 cm.

Sources: GBIF (CC BY 4.0), USDA PLANTS and Trefle (CC BY 4.0). The care and design notes are LandscapeGPT's own.