<em>Ginkgo biloba</em>, maidenhair tree: planting, care and uses

Description and botany

A true living fossil, Ginkgo biloba, also called “maidenhair tree” or “silver apricot“, appeared on Earth during the Jurassic, about 190 million years ago. It is now the last surviving representative of its family, the Ginkgoaceae, the oldest botanical family still present on Earth, which appeared nearly 270 million years ago.

Native to south-east China, in the Tianmushan mountains, it now survives hardly at all in the wild. Its conservation status is listed as “endangered” and the Tianmushan nature reserve was created to continue protecting the last wild specimens and this very particular biotope.

Cultivated in China for millennia and in Japan and Korea since the 12th century. It only reached Europe in 1730, at Utrecht. In France it was brought back by Auguste Broussonier in 1778 and planted at the Jardin des Plantes in Montpellier. A cutting from that specimen was taken and planted in 1795 at the Jardin des Plantes in Paris. Both are still alive and in good health today.

Slow-growing in its early years, Ginkgo biloba can become very large, over forty metres, and live for a very long time. Some planted in Asia are millennia old. According to Francis Hallé, it could even be considered immortal since no predator, disease or parasite is known to affect it. Only climatic hazards or the woodcutter’s axe can put an end to it. Even a nuclear explosion was not enough… Indeed, Ginkgo biloba was the first tree to regrow in Hiroshima after the war.

→ To learn more about the secret of its longevity, we recommend reading this article: “No planned obsolescence for Ginkgo biloba!“

Ginkgo biloba – lithograph by Philipp Franz von Siebold and Joseph Gerhard Zuccarini

Its deciduous, palmate foliage is bilobed (hence the species name “biloba“) and petiolate, with leaves grouped by threes or fours on short shoots. Leaves are more notched on female trees (see below). Initially light green, foliage turns a striking golden yellow in October. Its brown-grey bark is at first smooth then, over time, cracks and fissures. On trunks of aged specimens form tchitchis, outgrowths resembling udders.

It is a dioecious plant, meaning there are male and female trees. Male trees form small aments that disperse pollen and female trees bear naked flowers, without floral parts. These transform into ovules which, once on the ground and fertilised by pollen, release a particularly unpleasant rancid-butter smell (butyric acid). Therefore favour male trees. In fact, all selected varieties are males, to avoid this minor nuisance. Do not confuse the ovules, those small yellow-brown fleshy balls, with fruits or seeds. Indeed, ginkgos are classed among the Prespermaphyta, so they do not produce fruits or seeds, which implies that the ovule once fertilised must germinate as quickly as possible, often at the foot of the tree. The young tree thus formed will not be sexually mature, at the earliest, before 15 years.

Ginkgo biloba prefers to grow in full sun. It is very hardy, very resilient and very tolerant regarding soil. An ordinary, well-drained soil, even slightly calcareous, suits it, but it does not appreciate stagnant moisture. It tolerates drought, wind and air pollution.

In youth, Ginkgo looks like a kind of large skeletal broom, then, over the years, adopts a broad upright habit with very short shoots. The male specimen has a more erect habit while the female adopts a more spreading habit and is a little less vigorous. There are columnar varieties (such as ‘Blagon’ for example) or weeping types (the ‘Pendula’ variety).

Foliage of Ginkgo biloba through the seasons

Our favourite varieties

Ginkgo biloba - Maidenhair Tree

Type species. Splendid as a solitary specimen in a sunny garden. Requires substantial space because, besides sometimes spectacular height—up to twenty metres—its width of about ten metres may exclude it from small gardens.

• Height at maturity 15 m

See the product sheet

Ginkgo biloba fastigiata Blagon

Ginkgo biloba 'Blagon' is much less imposing than the previous one. Its fastigiate habit gives it a maximum width of two metres, allowing it to be happily inserted into a modest-sized garden.

• Height at maturity 10 m

See the product sheet

Ginkgo biloba Mariken

Ginkgo biloba 'Mariken' grows slowly and reaches two metres only after many years. As sumptuous in autumn as the type species, its bilobed leaves are, however, smaller and slightly puckered.

• Height at maturity 2,50 m

See the product sheet

Ginkgo biloba Troll

A true little botanical gem, Ginkgo biloba 'Troll' is perfect for cultivation in a pot or as a bonsai, since it does not exceed one metre in any direction. It will also make a striking addition to a Japanese-style rockery.

• Height at maturity 1,10 m

See the product sheet

Planting a Ginkgo biloba

Exposure and soil

Ginkgo biloba is very easy to grow and appreciates sunny positions. Regarding soil, it is not fussy: ordinary garden soil, even if poor, stony or calcareous, suits it. Only thing it dislikes in soil is stagnant moisture.

Planting time

Wait until spring, after frosts (March–April), to plant your Ginkgo biloba as a root ball or in a container. You can also, like other conifers and evergreens, plant it at start of autumn in October to ensure good rooting before winter. Prefer young trees for reliable establishment.

How to plant a Ginkgo?

In open ground

• Immerse container in water for a few hours to rehydrate root ball
• Remove your plant from its pot but do not break up the root ball
• Make a hole twice the width and twice the depth of the root ball
• Ginkgo has a primary tap root that will anchor the tree in soil before adventive roots develop. Consequently, it is preferable to loosen soil deeply at bottom of hole.
• Once soil is loosened, place a few handfuls of well‑rotted compost; you can add a little sand if soil is compact
• Place root ball at bottom of hole and backfill with excavated soil
• Firm surface and give ten litres of water to avoid any air pockets
• Place a mulch (dead leaves, grass, …) which will help your tree through a period of summer drought and/or a spell of frost in winter, at least during those first years

In a pot

• Immerse container in water for a few hours to rehydrate root ball
• Remove your plant from its pot but do not break up the root ball
• Choose a container with a volume twice that of the root ball. Make sure there are one or more drainage holes!
• Use a mix of 1/3 potting compost – 1/3 ordinary garden soil – 1/3 sand to provide rich but light, well‑draining soil
• Place a draining layer of small gravel at bottom of pot then a layer of your soil mix about one‑third of pot height
• Place root ball in pot and backfill with your soil mix
• Firm surface and water well to avoid any air pockets
• You can place a “mulch” around the trunk with pebbles or bark. Please note: for a bonsai, technique remains identical but you will need to prune nearly half of the roots with a pair of cutters sterilised with alcohol. Cut should be fairly deep, at least 15–20 centimetres deep. In winter, shelter tree in a frost‑free location. Soil mix can be 70% Akadama and 30% potting compost for better drainage.

Multiplication

By sowing fertilised ovules

You can simply collect gently young shoots that have germinated under an adult female tree or pick up some ovules fallen to ground. Dip collected ovules in water at 70°C for five minutes so outer covering cracks. If not in a hurry, place ovules for stratification in moist sand over winter (less effective in my experience). Sow immediately under cover in bonsai potting compost or in a light, well-draining soil (half compost – half sand). Keep young plant for one year before transplanting into open ground.

Ginkgo biloba ovules

By propagation by cuttings

Take short lateral shoots that are semi-ripe, that is, a shoot of the year that has begun to become lignified at base but remains soft at tip. Remove leaves except two or three at tip. Most leaves are always removed from a shoot or branch to be propagated; this prevents excessive evapotranspiration while keeping some for photosynthesis. Coat tip with rooting plant hormones or dip into a little water in which you have left a few willow branches for one or two nights (a natural, free rooting plant hormone!) to facilitate root formation. Insert shoot into a mix of potting compost and sand. Wait a few months after rooting is clearly visible before planting tree in open ground.

By air layering

Strip bark from a branch you wish to layer. Surround this wound with moist sphagnum and wrap everything with a plastic bag pierced with holes and secured with raffia. Spray daily to prevent drying out. As soon as roots appear in this ball of sphagnum, you can pot up into a light substrate, half potting compost and half sand. Wait a few months before planting in open ground. This method is ideal for obtaining bonsai with a contorted or slightly twisted habit.

By lateral graft

On a young Ginkgo biloba seedling (that is, species type), you can graft into lower part of trunk so that later soil hides graft point. Split rootstock vertically for two centimetres with a grafting knife. The idea is to incise a few millimetres deep and open this wound by separating the bark. Place into this slit a branch cut on the bevel from variety you wish to reproduce. Wrap with raffia and tie firmly (personally I use large clothes pegs if rootstock is not too wide, which allows me to remove them and check there is no rot, main cause of graft failure). This method is perfect for multiplying a specific variety and should therefore be reserved for professionals or experienced amateurs.

Ginkgo biloba : care, pruning and maintenance

Care

During its early years, keep some moisture at the base of the tree. But not too much! In short, a simple mulch of herbs or dead leaves and, from time to time, a watering can if summer is particularly dry, and your Ginkgo will thrive.

Pruning

Although a favourite subject for bonsai and extremely hardy, even tolerating harsh treatment, Ginkgo biloba does not particularly like pruning. If you can avoid it, do so! This will spare your tree unnecessary wounds and an unbalanced structure.

Diseases and pests

To date, no disease, pest or parasitic organism is known to affect Ginkgo biloba.

Companion planting and uses

Alone, certainly, but in a beautiful setting…

Ginkgo biloba is a marvel simply placed on its own (standing proud!) at the centre of a short grass meadow. But… do not forget to give it a strong contrast in the background, especially in autumn. In that case, take from your hat (straw one) some conifers and evergreens with dark or bluish foliage. For example, this striking Pinus nigra ‘Molette’ or the ever-charming Picea pungens ‘Jeddeloh’ whose bluish thorns will contrast with the golden-yellow autumn foliage of Ginkgo, and why not a handsome Magnolia grandiflora ‘Alta’ whose evergreen dark green foliage will reinforce the tender green of our “tree of forty coins”. Do not place these too close to one another; after all, they are an ocean apart in their natural medium… To dress the base of your Ginkgo biloba, a tapetum of Pachysandra terminalis will be a good idea if your tree provides them with enough shade.

A pairing idea: Ginkgo biloba, Picea pungens ‘Jeddeloh’, Magnolia grandiflora ‘Alta’ and Pachysandra terminalis

In a zen corner of the garden

In the quietest corner of your garden, the spot where even your annoying neighbour dares not interrupt your meditation for fear of incurring your wrath: plant Ginkgo biloba ‘Blagon’ alongside an Acer shirasawanum ‘Jordan’ with autumn colours as vivid as its companion, a charming Prunus serrulata ‘Amanogawa’ with a habit as fastigiate as its golden-foliaged friend and a tapetum of Hakonechloa macra. Your garden has suddenly travelled roughly 10,000 km to find itself in the Land of the Rising Sun. Moshimoshi!

An example of a Japan-inspired pairing: Ginkgo biloba ‘Blagon’, Acer shirasawanum ‘Jordan’, Prunus serrulata ‘Amanogawa’ and Hakonechloa macra

For a terrace with a chic, contemporary vibe

Ginkgo biloba ‘Mariken’ will be in good company with other Asian companions. The flowering of Camellia botanyuki will brighten your terrace in winter while Ginkgo will be nowhere to be seen. Add striking, elegant architectural foliage in the form of a Fargesia murielae (do not forget to water it!). We still lack flowers in season… add two evergreens: the handsome Escallonia ‘Pink Elle’ with spectacular summer flowering and, for scented presence, a Choisya dwarf ‘White Dazzler’. 

An example of a terrace pairing: Ginkgo biloba ‘Mariken’, Camellia ‘Botanyuki’, Fargesia murielae ‘Panda’, Choisya ternata ‘White Dazzle’ and Escallonia laevis ‘Pink Elle’

In a rock garden, lost among a collection of dwarf conifers

The adorable Ginkgo biloba ‘Troll’ (what a name!) will be so original amid all those dwarf conifers and evergreens: a Chamaecyparis obtusa ‘nana’, a Cephalotaxus harringtonia ‘Korean Gold’, an Abies koreana ‘Kohout’s Icebreaker’, a Pinus densiflora ‘Alice Verkade’ and other Cryptomeria japonica… Who said conifers were cumbersome?! A tapetum of Erica carnea will serve as an attractive groundcover.

A rock garden pairing idea: Ginkgo biloba ‘Troll’, Cryptomeria japonica ‘Vilmoriniana’, Chamaecyparis obtusa ‘Nana Gracilis’, Abies koreana ‘Kohouts Icebreaker’ and Pinus densiflora ‘Alice Verkade’

Useless anecdotes

• Pseudo-seeds are eaten in Asia roasted like pistachios once the fleshy part has been removed; raw they are toxic.
• Pale-yellow wood of Ginkgo is used in cabinetmaking and sculpture
• Slipping a few Ginkgo leaves into books would keep insects away
• Ginkgo is also cultivated for medicinal use. Its medicinal properties (venous disorders, cardiac regulator, …) have been known for millennia, although recent studies report a non-significant effect. Research is currently under way into combating Alzheimer’s disease and Parkinson’s disease, without success so far.
• Surprisingly and exceptionally, monoecious Ginkgo trees (male and female flowers on the same tree) can occur in the wild, with no plausible explanation for this phenomenon.
• Its nickname “tree of forty écus” would come from the fact that the French botanist Mr de Pétigny supposedly bought from another botanist, this one English, five Ginkgo biloba for the staggering sum of 40 écus per tree. (which is undoubtedly far more expensive than in our nursery!)
• It is also called “tree of a thousand écus“, doubtless referring to the golden colour Ginkgo adopts in autumn.
• A symbiotic micro-alga of the genus Coccomyxa lives in sym symbiosis within the very cells of Ginkgo Biloba. This type of endosymbiosis is unique on Earth.
• Ginkgo leaf is the symbol of the city of Tokyo while the tree itself is the symbol of… Weimar in Germany.
• tchitchis, these nipple-shaped outgrowths on ageing bark, used to serve as good-luck charms for wet nurses and young mothers.