To walk in the Arnold Arboretum’s juniper collection is, in some sense, to walk among garden specimens that could have been. For many gardeners, junipers—that is, the horticultural members of the genus Juniperus—are the classic case of the right plant in the wrong spot. How many times have new owners of old homes, with justified relish, pulled out sprawling juniper shrubs that have engulfed the porch? How many times has a chainsaw licked the fragrant wood of an eastern redcedar (J. virginiana) at the corner of an old foundation, where the once-small tree has outgrown its footing? But in the Arboretum’s juniper collection, the plants have the luxury of both time and space. This combination, coupled with decades of horticultural care, has offered an opportunity for the plants to do what specimens elsewhere have not. These junipers have made it—out of the horticultural past, into the present.
On one slope, edging into the collection of hornbeams (Carpinus), a plantation of centenarian junipers—mostly eastern redcedars—point to European nurseries and gardens, with whom the Arboretum would exchange plant material at the turn of the twentieth century. (See, for instance, accession 14887*A.) How curious to see named varieties of this North American species coming back to the United States, after a formative schooling in European nurseries like Simon-Louis Frères, a nursery near the French-speaking city of Metz, then part of Germany; K. Wezelenburg & Sons, located near Boskoop, Netherlands; and L. Späth, in Berlin, which was then considered the largest nursery in the world. The trees are now mature alumni from the pre-World War era, with sturdily sculpted trunks—the sinewy bark splitting into fibers, like cut pieces of twine.
When Charles Sprague Sargent wrote about the eastern redcedar, in Garden and Forest, in 1897, just four or five years before many of the trees in this plantation began arriving at the Arboretum, he had resounding praise for the species. “So much has been said in the columns of this journal about the value of Juniperus virginiana as an ornamental tree that it seems unnecessary to say more on the subject,” he wrote. “No other tree is more formal in one of its forms and more picturesque in an other. None of our trees are better suited to cover a rocky knoll, or, mingled with trees of less formal outline, to give interest and variety to the landscape.” These days, gardeners can find horticultural varieties of the eastern redcedar at most garden centers, but the species is one that has been simultaneously used often—but poorly—and not enough. Horticulturist Michael Dirr’s assessment of the unfulfilled promise for the species, which first appeared in his 1998 edition of the Manual of Woody Landscape Plants, still seems to be true: “I suspect that the best days are ahead.” (It’s worth noting that, in the Great Plains, the species is now considered invasive.)
To walk through the Arboretum’s juniper collection, moreover, is to think of shape and form. How could someone not revel in the weeping contours of the needle juniper (Juniperus rigida), especially as the plant enters old age? The most impressive specimen of this species (accession 14866*K), located in the center of the collection, was grown from seed that Sargent collected in Japan in 1892. The smaller lateral branches droop from the main frame like drop cloths on a piece of furniture or like ghostly streamers on a Halloween tree—a Charles Addams phantasm. To walk through the Arboretum’s juniper collection is to search for similes, to stretch for language. Sargent’s tree arises on three primary leaders, and when I brushed beneath the outer branches—parting them like willow branches—and stepped beneath the canopy, the sun shone through, illuminating the long needles like delicate glasswork.
Then, too, there are the low, scrambling junipers. My favorite among them, near the Sargent tree, is imbued with a bluish tone, and the branches bend in a delicate curtsy. It’s actually a tight grouping of four plants, all a cultivar known as the Meyer singleseed juniper (Juniperus squamata ‘Meyeri’, accessions 10316 and 249-42). One of the older plants, which was obtained, in 1919, from Hicks Nurseries—a company on Long Island, New York—rises on a semi-upright upright trunk, while the other three plants cascade around it. It’s worth viewing the plants from all angles, watching as the waves of foliage shift and move. If the light is right, the composition is textured and dramatic—a swelling sea. To walk through the juniper collection is, I dare say, to walk through one of the most curious spaces at the Arboretum—especially in winter—a landscapes of fantasy and light.