Considered living fossils, ginkgo trees are among the last of their kind. These stunning 25 to 80-foot-tall trees have uniquely fan-shaped leaves that turn vibrant golden-yellow in the autumn. As the last surviving members of the ancient Ginkgoacaeae plant family, these tremendous trees are geological relics that make enchanting landscape specimens for fall color.
Although they are native to China, these trees grow well in most parts of the United States, from USDA zones 3 through 9. Ginkgos are known for their memory-enhancing herbal qualities, but the seeds of female trees can also be quite stinky if left on the ground. Fortunately, seedless all-male cultivars are now available to avoid the smelly cleanup.
Let’s dig into everything you need to know about planting and growing this living fossil in your yard!
Overview
The Ginkgo tree is a deciduous tree classified under the genus Ginkgo.
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History and Cultivation
Native to China, ginkgo trees have been admired for hundreds of thousands of years in gardens, ornamental landscapes, and urban parks. The oldest known ginkgo tree in North America is located in South Philly’s Bartram’s Garden, allegedly planted in the 1700s. But the oldest ginkgo in the world is over 3,000 years old and grows outside a Buddhist temple in Xi’an City, China.
The long-lived trees show no signs of slowing down, and many speculate that they get more vibrant and healthy as they age. In the fall, the ground beneath each tree is shockingly blanketed with golden-yellow leaves that shine through even the foggiest days. If you plant one in your yard, you can enjoy an equally stunning show that will reliably return every year for generations to come.
What is Ginkgo Biloba?
It is an ancient tree with a pyramidal shape and golden leaves in fall.
Ginkgo biloba is among the oldest living tree species. The deciduous tree is the last remaining species of the ancient Ginkgoacaeae family. Sometimes called maidenhair trees, the distinctive fan-shaped leaves turn extraordinarily bright yellow in the fall.
The massive trees grow up to 80 feet tall and can live for thousands of years, earning them the title of “living fossils.” Gingko is notable for its medicinal qualities for the brain and memory. The tree’s extracts have been used as an herbal medicine for many centuries, and modern science has proven the neurological benefits for memory enhancement, as well as prevention of dementia and Alzheimer’s disease.
Intriguingly, this ancient tree is quite tolerant of drought and urban pollution, making it a popular landscaping tree for city streets, parks, and buildings. It is virtually pest-and-disease-free and tolerates cold weather. The trees can be planted as large single-specimen shade trees or at a closer spacing for a privacy hedge. The pyramidal shape and few branches make for a striking focal point, and the fan-shaped leaves turn from pretty green to striking gold every fall.
Key Attributes
Ginkgo seeds are renowned for their unpleasant smell.
Gingkos are dioecious, meaning they have separate male and female trees. The male trees are preferred for cultivation because the female trees can be stinky. Female trees produce yellow cherry-like “fruits” that dangle in pairs. The fleshy fruit-like structure is actually a seed that resembles a plum seed or a nut. These nuts are traditionally used in soups and medicines.
Gingko “fruits” are not technically fruits, but rather fleshy seed ovaries. They are notoriously stinky when they fall to the ground. A gorgeous row of ginkgos grew on my college campus and regularly shed their “fruits” on the ground every fall. The orangish-tan fleshy seeds were so pretty, yet they smelled like vomit as they rotted on the concrete. It is a smell you will never forget! Horticulturalists have struggled to properly sex-identify the trees when they’re young, but by propagating with cuttings or using the male-only cultivars that we will discuss below, you can ensure a sleek, stink-free landscape.
The trees naturally grow straight up with a pyramidal structure averaging 40 to 80 feet tall but often exceeding 100 feet at maturity. Dwarf varieties are also available. The bark is fissured and gray with a corky texture. As trees age, the bark becomes more deeply furrowed like an ancient wrinkled wise being. The interior wood is light-colored and soft and was once used for religious furniture. However, it is too soft to serve structural purposes, and nobody wants to cut down a living fossil!
Gingko leaves are fan-shaped with irregular toothing along the widest edge. There is a distinctive notch that splits the leaves into two lobes, hence the name bi-loba, as in “two.” The leaves are cheery lime green and turn dull and grayish in the summer, then yellow and eventually gold in the autumn. They stay on the tree late into the season for long-lasting color, then rapidly fall at the same time, creating a pretty skirt of gold. The leaves are most commonly used in herbal extractions for memory-enhancing supplements and teas.
Where Do Ginkgo Trees Originate?
Planting this tree helps conserve a highly endangered ancient species.
These tremendous ancient species are native to China and grow throughout the world as ornamental and medicinal plants. Ginkgo biloba trees date back over 270 million years to the Permian Period when Earth’s crustal plates were still in the single continental formation of Pangea. About 70% of terrestrial plant and animal species on Earth went extinct during this era, but the majestic ginkgo survived.
Ginkgo trees are widely cultivated but are listed as highly endangered in the wild. Planting one in your yard can help preserve an ancient species (though clearly, ginkgos don’t need much help from humans to survive through the ages).
Propagation
An interesting fact about ginkgos is that they are gymnosperms, which means “naked seed” in Latin. These trees are so old that they pre-date flowering plants! Most gymnosperms are coniferous, like redwoods, pines, and firs, but ginkgos are broadleaf gymnosperms.
While their dangling “naked seeds” look similar to fruits, they are technically naked ovules or kernels with a fleshy covering. The trees don’t produce any flowers; instead, the pollen from a male tree reaches the open ovules of a female tree, and they fertilize each other.
While you can propagate ginkgo from seed, it is more common to propagate by cutting so you can ensure you have a male tree that won’t drop any stinky seeds in your yard. Grafting is sometimes used to jumpstart a new tree.
Cutting
Select young, healthy stems with fresh green leaves for taking cuttings.
The best way to replicate a ginkgo is by cutting. If a neighbor has an established male tree or you want to expand your collection, this is the most reliable way to ensure your landscape doesn’t fall victim to a stinky female tree. Cuttings are the most reliable way to ensure the sex of the tree. They are simply little pieces of a tree’s twigs that form roots and grow into new saplings.
Take cuttings in early to mid-summer, around May through July. Find young or half-ripe wood that is greenish-tan and pliable but firm enough to handle like a twig. The stem should have plenty of fresh green leaves and no signs of disease.
To propagate by cutting:
- Find a half-ripe stem about the thickness of a pencil.
- Use sharp, sanitized shears or a knife to take a cutting five to seven inches long.
- Make a second diagonal cut on the bottom so the lower edge is in a V-shape.
- Remove the lower third of the leaves.
- Optionally, dip the V-shaped end in a rooting hormone.
- Prepare a pot or cell tray with a well-drained propagation mix, such as half peat moss and half vermiculite.
- Place the cutting in the soil blend, submerging about one-third of the stem.
- Leave the upper leaves above the soil surface.
- Optionally, cut the top leaves in half to reduce their surface area and promote new leaf growth.
- Keep consistently moist but not soggy.
- Place in a location with bright, indirect sunlight and wait until cuttings form roots.
Ginkgo cuttings may take six to eight weeks to root, and are typically ready to plant by the following spring. Give the stems a gentle tug to see if there is resistance holding them in place. You can leave them outside or in a ventilated greenhouse until they are ready to pot-up or transplant into the ground.
Grafting
This requires practice to master due to its complexity.
Grafting is a method for splicing a specific tree onto a vigorous rootstock. Some growers splice branches of male trees onto female tree rootstock. This allows a female tree to be fertilized without any other trees nearby, resulting in more diversity in the offspring, which could be helpful for future disease resistance or the development of new cultivars.
While fertilized female trees are generally undesirable for a landscape or home gardener, they are important for true ginkgo lovers who want to support future generations and genetic diversity in this living fossil tree. However, grafting is fairly advanced and may take some practice to master.
To graft this ancient tree:
- Start with an established female tree rootstock.
- Take softwood or semi-ripe cuttings from a male tree (scion) in late spring or early spring while the trees are still dormant with no signs of buds or growth.
- Ensure that the branch of the rootstock is the same thickness as the branch of the scion.
- It is common to use a whip-and-tongue graft with this species.
- Use a sharp, sanitized grafting knife to make a slanted cut at the bottom of the scion twig, about a 45° angle.
- Make two cuts downwards into the middle of the scion about one half to one inch deep like a “V.” This is the “tongue” of the graft.”
- Now, make an angled cut on the rootstock twig at a 45° angle.
- For the rootstock, cut a “V” down into the middle of the stem, creating an insert for the “tongue.”
- Join the two pieces together so the scion fits inside the rootstock, hugging each other.
- Wrap in grafting tape or string and cover with grafting wax or beeswax to conserve moisture.
Protect the graft for a couple of weeks to months while it heals. Once a new bud begins growing above the graft, you can remove the tape and check that the twig wound has healed, effectively splicing the two stems together.
Seed
Store the seeds in the refrigerator until ready for outdoor planting.
These prehistoric trees have unique seeds encased in a fleshy ovary that resembles a fruit. You can propagate fertilized ginkgos from seed, but beware that you will not know the sex of the resulting trees. Most seeds will become male trees, but you could accidentally plant a female tree and not find out until 5-10 years later when it begins fruiting.
To collect and germinate seeds:
- Find a “fruiting” female ginkgo in the fall. Follow your nose, as they tend to stink!
- Wear gloves to collect the ripe seeds.
- Remove the fleshy coating around the seeds, then wash them and lay out to dry on a paper towel.
- Store them in the refrigerator until you can plant them outdoors.
- You can sow the seeds outside in the fall or wait until spring.
- Scarification helps awaken the seeds from dormancy. Use a knife, sandpaper, or file to mechanically scratch the seed coating.
- Soak the seeds in warm water for about 24 hours.
- Plant in moist soil at a depth twice their largest dimension and place trays in an area with bright light.
The seeds can take up to 30-60 days to germinate and several years to mature. Nurture the young saplings in a greenhouse, windowsill, or open protected area until they are ready to transplant into the ground.
Planting
Whenever you plant a majestic ginkgo, you are prolonging a race of the world’s oldest living trees. This exciting endeavor is fairly simple as long as you choose the right location and practice patience while the ancient tree gets established.
How to Transplant
Pruning early promotes a strong central trunk and pyramidal shape in trees.
The best time to plant is in the early spring, just before saplings awaken from dormancy. The tree may have a few buds on it, but it’s best to plant before it has developed leaves. This timing encourages the sapling to channel its burst of spring energy into root establishment in its new home.
The transplanting process is similar to most saplings:
- Purchase or grow a baby gingko at least 12-16” long with a strong root ball.
- Select a site in full sun and proper spacing for the variety (see below).
- Amend the soil with sand, compost, or perlite to improve drainage.
- Soak the root ball in a bucket of water to prepare for planting. If the soil is already moist, skip this step.
- Dig a hole twice as wide as the root ball and about one and a half times as deep.
- Gently remove the sapling from its container, handling it from the stem.
- Place the sapling in the hole, ensuring the roots are fully buried and the soil level remains the same as it was in the container.
- Backfill the hole and press down slightly.
- Water regularly and ensure consistent moisture in hot, dry weather.
- Fertilization is not necessary, but you can add a handful of slow-release organic fertilizer in the hole at planting.
Early pruning is desirable if you want your tree to have a strong central trunk (also called a central leader) and pyramidal shape. Wait until the following winter after planting to remove lateral branches and select the central stem to be the leader.
Spacing
Privacy hedges and dwarf ginkgo varieties can be spaced closer together.
Reaching 40-60+ feet in height, ginkgos are very large single-specimen trees that need lots of space to thrive. It is recommended to plant a minimum of 10 feet from buildings, power lines, and other trees. Urban planners typically go further to ensure at least 20 feet of space between ginkgos and street lights or other large trees. At full maturity, this wise old species develops a canopy that can spread to an incredible 25-40 feet. The more space, the better.
Privacy hedges and dwarf ginkgo varieties are the only exceptions to this rule. A privacy hedge looks nice with regular spaced intervals of 8-12 feet between trees, but keep in mind that saplings at this spacing will not reach their fullest potential. You can space compact and dwarf varieties as close as 30-40” or grow them in containers.
How to Grow
These prehistoric trees have been on Earth for an estimated 200 million years, so they don’t need much help from humans to thrive. However, most gardeners are growing them outside of their native range in Asia.
Therefore, a few steps can ensure a strong establishment for another couple hundred million years in your yard. Your ginkgo will surely remain standing long after you, your house, and your great-great-great-grandkids are gone.
Light
This ancient tree creates pleasant shade for relaxation.
Full sun is ideal for this golden ancient tree. At maturity, these trees make delightful shade trees to sit underneath and enjoy a book on a hot day. They can survive in the partial shade of other trees, but it will dampen their potential and stunt their growth.
Water
Foster healthy root growth by watering plants deeply but infrequently.
You only need to water a ginkgo at the time of planting and during the first year if there is no rainfall. These trees are fairly drought-tolerant and do not like soggy soil. It’s important to avoid waterlogging by thoroughly amending the soil for drainage.
Deep, infrequent watering is better than shallow, frequent watering. In other words, it’s best to thoroughly drench the root zone when dry and allow it to almost dry out before watering again. Deep watering promotes deeper roots, while shallow watering can cause stunting. In areas with ample rainfall, there is no need to add supplemental irrigation. Once the tree is rooted in place (after the first two to three seasons), it should be able to get by solely on rainfall.
Soil
Ideal soil pH for the plant ranges from 5.0 to 8.0.
These trees grow best in sandy soil and prefer plenty of drainage. However, they are tolerant of some compaction, which is why they often grow in urban areas. Still, if you want your tree to grow as rapidly as possible, it’s best to amend the soil with horticultural sand, perlite, or compost. In heavy soils, you can double-dig the sapling hole to make it easier for the baby roots to spread outward and down.
Slightly alkaline soil is ideal, but this resilient species tolerates a pH of anywhere between 5.0 and 8.0. Compost is the easiest pH-balancing and drainage-improving amendment for most gardeners.
Climate and Temperature
They display stunning autumn foliage in regions with moderate to cold winters.
Ginkgo biloba grows best in USDA zones 3-9. The trees are drought-tolerant but struggle in hotter, dryer climates. They tend to put on the most gorgeous autumn show in areas with moderate to cold winters that trigger bright gold leaves that drop in unison.
Fertilizing
Synthetic fertilizers have the potential to lead to overfertilization and nutrient burn.
These trees have subsisted on natural soil minerals and nutrients for millions of years, so modern fertilizer is clearly unnecessary. If you want to boost the growth of a young tree, it’s vital to use only a small amount of slow-release organic fertilizers that provide balanced ratios of NPK. Synthetic fertilizers are not recommended because saplings are sensitive to overfertilization and nutrient burn.
Maintenance
Leaving autumn leaves to decompose provides natural nourishment or mulch.
Trimming is usually unnecessary for this naturally-rounded tree. However, early pruning is helpful for establishing the shape. It will create a strong central trunk rather than a branched or shrubby growth habit. You should only prune when the tree is dormant, during winter and early spring. This ensures that the tree can heal its wounds throughout the spring and remain strong as it enters the next season. Use sharp, sanitized shears to remove lower lateral branches, opting for a single central leader.
Mature trees don’t require any maintenance aside from removing dead branches or broken limbs.
Autumn leaves can be left in place to decompose and nurture the tree each year. If you rake them up, they also make excellent mulch in other parts of the garden.
Varieties
The comeback of this ancient tree has sparked many crosses and cultivars of Ginkgo biloba for use in urban landscapes and home gardens. At nurseries, you may also see this tree labeled as a maidenhair tree.
‘Autumn Gold’
The ‘Autumn Gold’ provides a vibrant golden autumn display without the hassle of smelly seeds.
The most iconic and commonly planted maidenhair tree in cities, ‘Autumn Gold’ has a broad conical shape that is highly desirable for street trees and front yards. This variety averages 40 feet tall, with a canopy spread around 30 feet. These trees average 12-24” of growth per season and appreciate regular watering while young.
Unsurprisingly, ‘Autumn Gold’ offers a striking golden fall display that will out-shine nearly every other plant in your garden. This is a seedless male cultivar, so there is no need to worry about smelly seeds falling in your yard.
‘Mariken’
A compact variety known as ‘Mariken’ is ideal for small gardens.
As a dwarf ultra-small ginkgo, this variety has short stubby stems with the classic full-sized lobed leaves. It grows in a rounded shape to about two feet tall and eight feet wide. ‘Mariken’ puts on only about two inches of growth per year but is long-lived like its cousins. This is a perfect cultivar for small-space gardeners who still want to enjoy the prehistoric wonders of this living fossil.
‘Jade Butterfly’
This vase-shaped dwarf cultivar grows slowly to about 12-14 feet tall.
The vase-shaped ‘Jade Butterfly’ dwarf cultivar has dense branching and bright green leaves. It is reliably seedless, so you don’t have to worry about the stink. This slow-growing deciduous tree slowly grows to about 6-12 feet tall and 10 feet wide. It has distinctive lobed maidenhair leaves and foliage that turns yellow-gold in the autumn.
‘Saratoga’
These trees display exceptional autumn foliage with light green leaves in summer.
Similar to ‘Autumn Gold,’ ‘Saratoga boasts extraordinary fall color. Its leaves are light green in the summertime, and it grows slightly faster than its counterparts. The all-male trees reach a maximum of 50 feet tall and have weeping leaves that are noticeably lighter than other varieties.
Garden Design
Consider shade-tolerant groundcovers to complement a ginkgo tree.
Gingkos tend to grow independently as central lawn specimens. Many varieties of grass cannot grow under the shade of a mature tree, so consider a shade-tolerant ground cover like violets, periwinkle, Japanese forest grass, or low-growing ferns. Ferns are my personal favorite because they add to the ancient, exotic vibe of a ginkgo. Companion shrub possibilities include rhododendrons, azaleas, and black elderberries.
Pests and Diseases
Accelerate growth of slow-growing trees by amending planting holes.
These trees are delightfully pest and disease-free. Deer leave them alone, and they almost never fall victim to pathogens. The only problem you may have with a ginkgo is root rot issues. Prevent root rot by planting in well-drained soil and avoiding overwatering. These trees do not like soggy roots.
If your tree is growing slowly, rest assured that this is common. These ancient trees are slow-growers, but you can speed up their growth by properly amending the planting hole and avoiding compacted soil.
Plant Uses
Ginkgo leaves are shown to improve memory retention and sharpen focus.
These trees are commonly used as landscape specimens and are most renowned for their medicinal uses as a brain-nourishing herb or supplement. The leaves are scientifically proven to improve memory and focus. The edible seeds were also traditionally consumed in soups and an ingredient in Chinese desserts, but some sources cite the seeds as toxic when raw or consumed in large amounts.
FAQs
Ginkgo biloba is the oldest surviving tree species on Earth, with fossil records dating back over 200 million years. This ancient tree is extraordinarily resilient, beautiful, and hardy. It has survived the Ice Age and doesn’t mind urban pollution. It also has a stunning golden fall color that makes it a delightful addition to landscapes and gardens.
Female gingkos produce stinky seeds that look like dangling yellow cherry clusters. When the seeds fall in the autumn, they tend to rot at the base and emit a putrid smell. The main drawback to growing this ancient tree is the risk of planting a female specimen, but most modern cultivars are seedless male-only trees.
Only female ginkgo trees are messy because they drop their smelly fruits at the end of the season. Fortunately, most landscapers and nurseries only offer seedless male trees that drop just gorgeous golden fall leaves. The leaves are best left in place or can be raked up and used as mulch in your garden.
Final Thoughts
If you’re ready to enjoy this ultra-unique prehistoric tree, all you need is an area with full sun, at least 20 square feet of space, and well-drained soil. To avoid the stinky seeds, source a male cultivar from a reputable nursery or take cuttings of a tree that you know does not produce them. Most importantly, plant your ginkgo in a place where it can thrive for a century or more— these trees are extremely long-lived, offering shade and beauty for generations to come.
