Dwarf Ginkgo Trees: Cousins of Conifers
Interested in cultivating a dwarf ginkgo tree? Discover a cultivar that works for you.
The world of dwarf Ginkgo cultivars is reminiscent of the mythical American West, with the lawman not always successful in dealing with those vigilantes and renegades who abound on the frontier of new plant introductions. Upstanding growers, plant breeders and enforcement organizations try vainly to provide order for collectors who, like the townsfolk in the movie High Noon, much to Gary Cooper’s dismay, secretly enjoy some of the disruptions which the outlaws bring.
This has made composing a list of “best of breed” dwarf Ginkgo more difficult than one might think. To the extent that readers are dissatisfied with the lack of specificity and clarity surrounding some of these suggestions, remember that unless collectors demand bonafides from retailers, and refuse to purchase without them, it will be difficult to halt the influx of incompletely documented plants into the market.
Many—if not most—growers and breeders are ethical, but there is little motivation for those who are at best sloppy and at worst dishonest to play by rules which collectors ignore. Does the draw of more offerings outweigh the confusion—and ultimately the disappointment—when a promised trait in a cultivar fails to materialize? Do those with small gardens or tight budgets enjoy wading through incomplete descriptions and conflicting information when selecting the cultivar for a choice location or container?
Remember, if we insist that plants which are distinctive from others be registered as new cultivars, with appropriate accompanying documentation, we could head to the nursery armed with the data, with which to choose the one likeliest to meet our criteria and please us the most. This dusty Western town could use some deputies!
Finding your right dwarf Ginkgo
Despite the challenges, we can still provide guidance in selecting a dwarf Ginkgo cultivar. If you want some degree of predictability, stick with those which have been around long enough and documented sufficiently to provide a reasonably clear idea of how the plant is going to perform. If you are more adventurous and want to explore the Ginkgo frontier, there are choices with less history which may tempt you. While the basic criteria for plant selection are more or less the same across genera, Ginkgo, due to the narrow range of characteristics discussed in Part I (one species, largely one sex, basically one color), really have only three attributes to consider: overall shape, size of plant and leaf shape/size.
Ordinarily, we would deem size to be the most important criterion, but these are all supposed to be dwarf varieties. Thus, in selecting one of these Ginkgo cultivars, it is generally most useful to first consider shape. Does the spot require a low spreader or a short, bushy plant? An upright, a vase-shaped or a columnar form? There are also pendulous versions, although most are not very weepy. Lucille Whitman, of Whitman Farms, a grower in Salem, Oregon, says that ‘Weeping Wonder’ is the best weeping form she’s seen. ‘Pendula’ and the others which purport to be weepers, really just have horizontal branches (Remember Richard Larson’s comment that “no Ginkgo is going to weep like a cherry.”).
A Look at Weeping Dwarf Ginkgos
Before you put ‘Weeping Wonder’ on your wish list, however, note that it is female, and if there is a male Ginkgo nearby, you may eventually get fruit. As we mentioned in Part I, fruit on a dwarf is unlikely to be particularly problematic, but caveat emptor. Richard Larson notes that ‘Weeping Wonder’ is a renaming of a plant which used to be called ‘Mutant Weeper’, and the plant eventually displays multiple morphologies, making its original name perhaps more useful!
‘Ross Moore’ is a more recent weeping introduction, but not much is known about it. So, we must wait to find out how it performs, and, since it was found as a growing tree, rather than as a broom on a sexed G. biloba, we as yet have no idea if it is a male or a female, or, indeed, how quickly it grows or how large it gets.
Size, indeed, is the second consideration in selection. Presumably those selecting dwarf cultivars are seeking small plants, but suggestions regarding size are famously defied—or at the very least, ignored—by collectors. With slow-growing plants such as Ginkgo, indeed it is the exceptional gardener who does not view size issues as the next owner’s—or even next generation’s—problem. Diane Van Anda, ISA certified arborist, says that proper size nomenclature and descriptions are often lacking in the nurseries and at the growers.
What is a Dwarf Ginkgo Tree?
The American Conifer Society has adopted the following definition for dwarf conifers, which we can reasonably apply to Ginkgo: growth per year of 1 to 6”, approximate size at 10 years between 1 to 6’. ‘Dwarf’ size is flanked by “miniature” and “intermediate”, and many growers do use these terms. However, there is wild variation in how they define them, and some add ‘semi-dwarf’, which is not universally recognized. Although widely used on tags, 10-year size is only useful if one knows how old the specimen in question is at purchase. Since the vast majority of dwarf Ginkgo come to market as grafted clones, they are not starting at year one in the same way that a seed grown plant is. So remember, when selecting a dwarf Ginkgo variety, that size is yet another unknown aspect of many on the market, and, if you wait long enough, your lovely dwarf tree may outgrow its location.
The trade has a vested interest in underselling the size and growth rate of trees. As Diane explains: “Dwarf selections are increasingly being sought by landscape architects, designers and contractors as good choices for plant material in the urban landscape where smaller size is a desirable attribute.” Steven Courtney, Manager of Michigan State University’s Hidden Lake Gardens and Curator of its Harper Collection of Dwarf and Rare Conifers, offers a useful tip for those of us planting dwarf Ginkgo cultivars, the growth rates of which (and thus 10-year sizes) are unknown: root prune your plant every year, so that, if it outgrows its spot and you have to move it, the job will be less stressful for both you and the tree. Use a narrow-headed shovel (keep it sharpened) and stick it straight down around the plant on at least three sides.
Leafing Through Dwarf Ginkgo Tree Details
The third consideration in selecting a cultivar is leaf detail; some, such as ‘Jade Butterflies’ have leaves similar to the species. Others sport tiny leaves. Still others have leaves which are oddly formed or variable, such as ‘Thelma’ or ‘Tubifolia’. For many Ginkgo aficionados, the iconic leaf shape of the species is desirable and they shun—or at least do not favor—the variations on some of the dwarf cultivars. In speaking with collectors and growers, I heard more vehemence about leaf size and shape than about any other aspect of Ginkgo! Thus, with a relatively short list of attributes to consider, what do experts— and collectors—recommend among the nearly 30 dwarf cultivars currently being marketed in the U.S.?
When pressed for her favorites, Lucille, a pragmatist, focuses on selections which are distinctive, reliable and reasonably available. For those looking for nicely shaped choices with leaves similar to those of the species, she suggests ‘Spring Grove’, which is essentially vase-shaped, or ‘Mariken’, which grows in a compact, shrub-like fashion, but is sometimes grafted onto a stalk. ‘Chris’ Dwarf’ (syn. ‘Munchkin’) and ‘Chase Manhattan’ are her choices for “little bitty leaves”. ‘Tubifolia’ (often incorrectly styled ‘Tubiformis’) is a slightly bigger dwarf, to 6’ or so in 10 years, and has leaves which, on mature wood, are fused at the base into a trumpetshape which is distinctive, or, as she says, in her Southern drawl, “kinda cute”.
She finds ‘Troll’ aptly named, with heavy limbs which project at odd angles and ‘Thelma’ to be the strangest one she’s seen, with a fringed, split leaf. Crispin Silva, of Crispin’s Creations Nursery in Molalla, Oregon has been propagating Ginkgo for about 20 years, beginning with some of the older selections such as ‘Chase Manhattan’, which is still a favorite, of both his and his customers. Crispin has seen increased interest in dwarf Ginkgo on the part of the public; folks visiting his small operation come seeking Ginkgo along with other specialty trees such as Japanese maples, dogwoods and Styrax.
Favored Dwarf Ginkgo Tree Cultivars
Gary Handy, owner of Handy Nursery in Boring, Oregon, is willing to commit himself and term ‘Spring Grove’ the best dwarf, although he admits that he is viewing it from a grower’s perspective. ‘Spring Grove’ has a much fuller appearance as a young plant—even in a gallon container—than any other dwarf cultivar. Thus, a retail customer gets a fatter, denser plant, even when small. That, by itself, may be enough of a reason to begin one’s dwarf Ginkgo collection with ‘Spring Grove’; small Ginkgo have a way of looking like so many sticks initially, with little in the way of branching. ‘Spring Grove’ is also more uniform in growth habit than others, such as ‘Jade Butterflies’ or ‘Witch’s Broom’, which can be more irregular. Gary admits that some people prefer such irregular shapes, so that it largely comes down to personal preference.
Richard Larson is also a ‘Spring Grove’ fan, but cautions that it should probably be termed an intermediate rather than a dwarf. He describes one that was planted in 1998 which is now about 10’ tall. He too likes ‘Mariken’, which he describes as “well behaved, low and compact and retains its compact status well”. He cites ‘Troll’ as another favorite. After 12 years his plant similarly has stayed compact and well behaved. Its name comes from its short, stubby branches which Lucille described as ‘heavy’.
Ironically, ‘Jehosephat’ (originally named Spring Grove #86), which Richard registered himself, has not lived up to his expectations, which should serve as a cautionary tale to all; he observed it for 12 years, after which the plant was still not even up to his knees. He then registered it, and shortly thereafter, following a mild, wet summer it “scooted up” to where it is virtually identical to ‘Spring Grove Sport’. If a diligent observer who believes in the integrity of the registration process can have this experience, what does that say about the reliability or differentiation of unregistered Ginkgo cultivars?
Steven Courtney’s favorites are ‘‘Jehosephat’, ‘Witch’s Broom’/‘WB’ and ‘Munchkin’ (syn ‘Chris’ Dwarf’). He likes the very full appearance of ‘Jehosephat’, which has leaves about half the size of the species. The densely-leaved, globe-shaped plant has very full branching so that the overall effect is one of lushness. ‘WB’ has stayed true to expectations—that is, quite dwarf—in his garden, where it has been growing for about five years. His sandy soil does not favor rapid growth, so that may be a contributing factor. He likes ‘Munchkin’ for its shape, which is broad and spreading, and for its tiny leaves. For tiny-leaved fans, it is worth noting that ‘Munchkin’/’Chris’ Dwarf’ has the smallest leaves of any Ginkgo.
Byron Baxter, who operates a small specialty nursery in Ohio, favors ‘Chi Chi’, syn. ‘Tschi Tschi’, which some label an intermediate. He specializes in conifers and niche plants not offered by many of the bigger growers; even though ‘Tschi Tschi’ is an older cultivar, and many more dwarfs have been introduced since it became available. He says that it fills a place in the landscape perfectly. “It is that perfect fit which makes both the tree and me happy. If only all of my plantings over the years had been sited as such, my gardens would be much better. Live and learn.”
Thoughts from Dwarf Ginkgo Tree Collectors
Collectors, not surprisingly, have their own opinions of which cultivars represent the “best of breed." Dave Stegmaier in Shawnee, Kansas, an avid collector of specimen conifers which he interplants with deciduous trees and shrubs, has a number of dwarf Ginkgo and favors ‘Jade Butterflies’. While he cautions that it is not a “stand alone, focal point” tree, it is an attention-getter all year round, with its dark-green butterfly-shaped leaves in spring and summer and its distinctive bark and vertical limbs in winter. Then, of course, there is the buttery-yellow fall color!
Jan Curry, who gardens in the San Francisco Bay Area, is so taken with ‘Mariken’, that, despite a small garden chock-a-block with specimen conifers and other intriguing shrubs and small trees, she is looking to find a place to plant a second one! ‘Mariken’ meets her criteria for being both small and interesting, and she likes its low, shrubby form. Jan is a perfect example of a collector who values some predictability in her selections; her garden is simply not large enough to accommodate failed choices or plants which grow faster or larger than they are supposed to.
Alan Twohig in Chesapeake, Maryland grows about half a dozen different cultivars, including ‘Munchkin’ (syn. ‘Chris’ Dwarf’), ‘Chase Manhattan’, ‘Troll’, ‘Jade Butterflies’ and ‘Mariken’. He has a ‘Witch’s Broom’/’WB’ in a container in a choice location by his front door. Dwarf trees are often wonderful candidates for containers and Ginkgo cultivars are no exception. Al admits that he may have to move it into the ground at some point, but for now it makes a lovely, eye-catching focal point on his porch. It lives there year-round, with winter interest provided by its interesting scaffolding. Al grew Japanese maples for about 20 years and notes that the dwarf Ginkgo make a great alternative to maples for a small deciduous tree amongst conifers, especially in smaller gardens with limited space. Al, who, like Jan, has a small garden, has stuck with the better-documented cultivars to avoid giving over prime garden real estate to plants which may prove disappointing.
This author has about 10 dwarf Ginkgo and finds ‘Todd’s Dwarf’ and ‘Mariken’ the most pleasing, largely due to the attractive branching and overall structure of the plants. I have to admit that I like the small leaves of ‘Chase Manhattan’ and the furled ones of ‘Tubifolia’. Wanting more predictability, I have stuck with the tried and true, but confess that the descriptions of ‘Beijing Gold’, despite being inconsistent, intrigued me so much that I purchased a small plant this year and am looking forward to seeing the leaf color for myself. I am also intrigued by descriptions of some of the spreading forms, such as ‘Girard’s Spreader’ and ‘Layin Low’, and the weeper ‘Ross Moore’, but cannot find out much about them—or indeed locate the plants for sale—so, I will leave those for others to try.
New Dwarf Ginkgo Tree Cultivars
For those of you who want to hunt for the very latest, in fact, one still in the “laboratory”, Byron Baxter, the Ohio tree buff, tells of liners he received some years ago for ‘Tubifolia’ (syn. ‘Tubeleaf’, ‘Tubiformis’). They grew as expected except for one, which never sent up a leader, and is now about 18” tall and 5’ wide. He grafted some of the wood in 2011, expecting it to revert and grow like the others, but all the grafts grew laterally—not a single one put up a leader. The trees grow laterally for about 3-4’ and then arch down to the ground.
Byron, who is the registrar for ‘Queen City’, one of the ‘Spring Grove’ witch’s brooms, sent in a registration for his find, calling it ‘Golden Arches’. An ACS member touring last summer pointed out that since the understock is short (18” or so), it is hard to know if the shape is really arched or only pendulous. Byron plans to graft onto higher understock this year to determine the ultimate shape of the tree. However, we may have to wait a while to learn the results: it turns out that scion wood is not the only wood which is in short supply in the world of Ginkgo grafts! Understock is not exactly prevalent, either.
When looking for three-foot understock for his high grafts, Byron could not find any. Thus, he is doing it the old-fashioned way and growing his own. Ginkgo futures, anyone? Dave in Shawnee, when searching for the best words to describe why he loves and enjoys Ginkgo, let the poet Howard Nemerov do it for him:
The Consent (by Howard Nemerov)
Late in November, on a single night
Not even near to freezing, the ginkgo trees
That stand along the walk drop all their leaves
In one consent, and neither to rain nor to wind
But as though to time alone: the golden and green
Leaves litter the lawn today, that yesterday
Had spread aloft their fluttering fans of light.
What signal from the stars?
What senses took it in?
What in those wooden motives so decided
To strike their leaves, to down their leaves,
Rebellion or surrender? and if this
Can happen thus, what race shall be exempt?
What use to learn the lessons taught by time.
If a star at any time may tell us: Now.
So, if you’re not growing at least one dwarf Ginkgo cultivar, what are you waiting for? The time is Now! Click here to read Sara's introduction to Ginkgo biloba and here to learn about variegated G. biloba.
This article was originally published in the Spring 2013 issue of Conifer Quarterly. Join the American Conifer Society to access our extensive library of conifer-related articles and connect to a nationwide group of plant lovers! Become a member for only $40 a year and get discounts with our growing list of participating nurseries in our Nursery Discount Program.