Ginkgo Tree

A living fossil and the last surviving member of an ancient plant family, with distinctive fan-shaped leaves that turn brilliant gold in autumn. Always plant male cultivars, as female trees produce foul-smelling fleshy seeds that create a slippery, malodorous mess on walkways. Ginkgos are virtually pest and disease free and extremely tolerant of urban pollution, compacted soil, and salt spray. They are slow to establish but ultimately form handsome shade trees that can live for hundreds of years.

Ginkgo trees are most reliably propagated through grafting of named male cultivars onto seedling rootstock. Growing from seed is possible but impractical for most gardeners, as seedlings take decades to reveal their sex and may produce unwanted female trees. If starting from seed, clean the outer flesh from fresh seeds, then cold-stratify in moist sand at 35 to 40 degrees Fahrenheit for 60 to 90 days. Sow stratified seeds one inch deep in containers and germinate at 65 to 75 degrees. Seedlings grow slowly in the first few years.

Select a planting site with full sun and well-drained soil. Ginkgo trees are exceptionally adaptable, tolerating a wide range of soil types including clay, sandy, and compacted urban soil with a pH from 5.0 to 8.0. Space trees at least 35 feet from structures and other large trees to accommodate their eventual broad canopy. Plant balled-and-burlapped or container-grown specimens in spring or early fall, setting the root flare level with the surrounding grade.

Water newly planted ginkgos deeply once a week during the first two growing seasons to establish a strong root system. Apply a 3-inch layer of organic mulch around the base, keeping it 6 inches from the trunk. Ginkgos are slow to establish and may appear to do little in the first few years while building root mass underground. Once established, they are remarkably drought-tolerant and require virtually no supplemental irrigation.

Pruning needs are minimal. Remove crossing or rubbing branches and maintain a strong central leader in the first decade. Ginkgos have few if any pest or disease problems and rarely need spraying. Always plant male cultivars such as Autumn Gold or Princeton Sentry to avoid the malodorous fruit produced by female trees. Ginkgos are among the most pollution-tolerant trees known and perform superbly as urban street and park trees.

Ginkgo trees have a light, open canopy that allows dappled sunlight to reach understory plantings. Spring-blooming bulbs like daffodils, crocuses, and tulips thrive beneath ginkgos, completing their growth cycle before the canopy fills in. Shade-tolerant groundcovers such as hostas, epimedium, and vinca provide attractive understory coverage. The fallen ginkgo leaves decompose slowly and make a good mulch layer. Avoid planting moisture-loving perennials directly beneath mature specimens, as established ginkgos can dry out the surrounding soil significantly.

Ginkgo trees are among the most soil-tolerant trees available, growing in clay, sand, loam, and even compacted urban soil. They prefer a slightly acidic to neutral pH of 5.5 to 7.5 but tolerate alkaline conditions well. Fertilize young trees in early spring with a balanced slow-release fertilizer for the first three to five years. Established ginkgos rarely need supplemental fertilization. Avoid high-nitrogen fertilizers that promote excessive soft growth at the expense of root development and structural wood.

Ideal Temperature

Hardiness Zone Compatibility

Female ginkgo trees produce fleshy, apricot-like seeds in autumn that emit a strong odor when the outer coating decays. If you have a female tree and wish to harvest the edible inner nuts, collect fallen seeds wearing gloves to avoid skin irritation from butyric acid in the flesh. Remove the outer pulp by soaking seeds in water for several days, then wash and dry the hard inner shells. Crack shells to reveal the pale green kernel inside, which must be cooked before eating as raw ginkgo nuts contain mild toxins.

Storage & Preservation

After cleaning and drying, ginkgo nuts can be stored in their shells in a cool, dry place for several weeks. For longer storage, shell the nuts and freeze the kernels in airtight containers for up to six months. Roasted ginkgo nuts can be kept in sealed jars at room temperature for one to two weeks. In Asian culinary traditions, ginkgo nuts are sometimes preserved in brine or vacuum-sealed after blanching to extend their shelf life through the winter months.

Troubleshooting Common Problems

The most significant problem is planting a female tree, which produces foul-smelling fruit that creates a slippery, offensive mess on sidewalks and patios. Always purchase named male cultivars from reputable nurseries. Ginkgos may experience transplant shock and appear dormant for the first year or two after planting. Slow initial growth is normal and not a cause for concern. Leaf scorch during extreme heat is cosmetic and does not indicate a serious health problem. The tree has virtually no significant pest or disease issues.

Growing Tips

1. Plant ginkgo trees in full sun to partial shade with deep, well-drained soil for best growth. They tolerate a wide range of soil types including clay, sand, and loam with a pH range of 5.0 to 8.0.
2. If you want edible ginkgo nuts, you must plant at least one female and one male tree. Most nursery stock is male to avoid the malodorous fruit, so specifically request female cultivars for nut production.
3. Space ginkgo trees at least 10 to 15 meters apart to allow for their broad mature canopy spread. Consider the eventual size of 20 to 35 meters tall when selecting a planting location.
4. Water newly planted ginkgo trees deeply once or twice per week during the first 2 to 3 growing seasons. Once established, ginkgo trees are quite drought tolerant and rarely need supplemental irrigation.
5. Apply a 7 to 10 centimeter layer of organic mulch around the root zone extending to the drip line, but keep mulch at least 10 centimeters away from the trunk to prevent moisture buildup and bark rot.
6. Prune ginkgo trees during dormancy in late winter to establish a strong central leader when young. Mature trees require very little pruning beyond removal of dead, damaged, or crossing branches.
7. Wear rubber or nitrile gloves when handling ginkgo fruit and cleaning the nuts, as the fleshy outer coating contains urushiol and ginkgolic acids that can cause contact dermatitis similar to poison ivy in sensitive individuals.
8. Propagate ginkgo from seed by stratifying cleaned seeds in moist sand at 1 to 5 degrees Celsius for 60 to 90 days, then sowing in spring. Named cultivars must be propagated by grafting onto seedling rootstock.
9. Ginkgo trees are exceptionally tolerant of urban conditions including compacted soil, road salt, air pollution, and restricted root zones, making them outstanding street trees and specimens for challenging urban landscapes.
10. Be patient with ginkgo trees as they are slow to moderate growers averaging 30 to 40 centimeters of height per year when young. Growth rate increases as the tree matures and the root system becomes well established.