December 2020 in the Garden

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I’m inclined to say that UBC Botanical Garden has much to offer at any time of year. Even in winter there are flowers, if you look for them. Berried plants are certainly abundant as well, but merely gazing upon the shape of a plant or the patterns of its leaves is often enough to evoke wonder or bring a satisfied smile. While many plants have a particular season of interest, there are plenty that fit the “pleasing to look at any time” category. For a December walk in the Garden, I’d like to point out some of my favourites.

When allowed to grow and spread under optimal conditions, China-native Viburnum davidii (Pere David’s viburnum) is a bold, exuberant shrub of rare beauty. Viburnum davidii is often maligned as coarse and altogether too common in the local landscape. But most commercial plantings are woefully mistreated and far too crowded to allow for natural growth. Doubters are encouraged to check out the vibrant specimen where Siebold Trail tees into Stearn Trail. The same foliar patterning is exhibited by the closely-related, but much larger-growing Viburnum cinnamomifolium (cinnamon-leaved viburnum). There are several plants in the Asian Garden: a large clump at the west end of Wharton Glade; a planting below the Ting (which is an excellent place from which to view it); and a lovely old plant on Lower Asian Way just east of the recently installed “Service Road.” Once they are a few years old, there is no confusing the two species, due to the height disparity. There are, of course, more subtle differences between them, but both exhibit red stems and stalks and enormously attractive leaves that have a glossy upper surface with three impressed main veins.

The deep green, oblong, papery leaves of Lindera erythrocarpa (red-berry spicebush) have only  recently turned bright yellow and dropped. The leaves are handsome, buoyant along the branches and reliably unblemished throughout the growing season, and serve as an appropriate accompaniment to the elegant, horizontally spreading branches. At least toward the end of the season, they are an effective foil for the prominent overwintering flower buds. Now that the leaves are gone, the ball-bearing-like buds, now reddened by cold, contrast wonderfully with the slender tips of the smooth, grey-brown stems. There is a specimen on Kingdon Ward Way at Upper Asian Way and another at the edge of the glade to the west of the Campbell Building, visible from the boardwalk, but it’s really worth having a close look.

I’ve been singing the praises of Cercidiphyllum japonicum for as long as I’ve had a platform to do so, but the pendulous cultivar ‘Morioka Weeping’, is, in a word, extraordinary, and worth an extra commendation. Originally discovered by Western botanists at Ryugenzi Temple in Morioka, Japan in 1635, this cultivar produces strongly upright stems with elegantly pendulous branches. The tree next to the pond by Straley Trail is perhaps the most outstanding example I know, and looks magnificent at any time of the year, clothed or not. Fittingly, there is a Botany Photo of the Day entry with a truly sensational image (with leaves) by Daniel Mosquin. We have a second specimen nearly as nice west of the Moon Gate on Upper Asian Way.

At the Moon Gate, Phyllostachys edulis (moso bamboo) takes centre stage. Its grey-green culms and stiff, compact, leafy side-branches present a very different aspect than most of the bamboos in the David C. Lam Asian Garden (they are all attractive, but many are decidedly droopy). With fewer than two dozen culms in the clump, this bamboo looks to be rather a benign species, but it is actually a seriously aggressive runner. Two years ago, a couple of underground rhizomes made their way more than 8 m away before terminating in above-ground culms. Soon after that discovery, a sand trench was installed around the perimeter of the clump, and since then, regular investigations with a sharp spade have proven sufficient to locate surreptitious rhizomes sneaking through (the sand makes it easier to cut them off). Moso bamboo is among the tallest growing of all hardy bamboos (up to 28 m in the wild!), and definitely one of the most attractive. Have a close look and make sure to run your fingers down the culms. They are covered in a vestiture of dense, velvety hairs.

There are many plants in the E.H. Lohbrunner Alpine Garden that fit the “attractive-at-any-time” description. One of my favourites is Genista radiata, a limestone-mountain endemic from southern Europe, which really doesn’t have a common name, at least in English. Some Internet Web sites give it the preposterous “rayed-branch broom.” I like to call it the “pine-needle broom,” as it looks as though someone has carelessly dropped a pile of fresh Pinus thunbergii (Japanese black pine) needles on their way through the garden. It is technically a deciduous shrub, but the leaves are so tiny and the stems so green that they’re barely missed after they drop in mid-summer. The stems really are fascinating: stiff, dark green, about the length of a pine needle and not much thicker, the branches horizontal and diverging at wide angles. Ultimately, plants mound up to 50 cm or so, but the youngest shoots maintain the dishevelled, pine-needle look that I find so appealing. Oh, and the flowers are nice, too.

In the Australasian section, Eucalyptus pauciflora subsp. niphophila (alpine snow gum) is another qualifier. While I wouldn’t discourage anyone from having a close look at the spectacular, blue-grey, white, olive and tan patchy bark, or the stiff, blue-green scimitar-shaped leaves, Eucalyptus in general have a habit of taking on a somewhat bedraggled appearance when one least expects it (invariably, this coincides with when one starts talking them up). In any case, the Garden’s snow gums, which are still small, were fantastic the last time I looked. Veronica topiaria (topiarist’s hebe) on the other hand, is always on its toes, aesthetically speaking. While other hebes may be damaged by cold, or wear out their welcome by falling open with age, this densely branched, low evergreen shrub always has the just-clipped-over look (in a good way). Topiarist’s hebe has a most unusual pewter-green leaf colour and a variety of interesting textures, depending on how closely one investigates, and it looks remarkable whatever the season.

Last, but by no means least, is Abies amabilis (Pacific silver fir). This species is native both in the local mountains (above about 500 m elevation) and all along the outer coast from Vancouver Island north to Alaska. Like other silver firs, A. amabilis produces horizontal tiers of symmetrically radiating branches. This is most obvious when plants are young. All of our specimens are in the BC Rainforest Garden, and our currently most attractive one was planted in 2002. It is a near-perfect specimen, about 5 m tall. Surprising to me, this tree has so far eluded the students who roam the campus every December looking for “free” Christmas trees (twenty years ago we lost the tops of several rare Asian firs to this thoughtless vandalism). Pacific silver fir is truly a beautiful and distinctive species. The grass-green needles are arranged in two flattened ranks on either side of the twigs—much like those of Abies grandis (grand fir), which is also native to southern British Columbia and the northwestern US, but at lower elevations, and also naturally, to the Botanical Garden site. The white, waxy undersides of the needles of both species (and all other Abies species) is what gives Abies the name “silver fir.” Unlike A. grandis, A. amabilis has an extra row of needles that point forward along the upper side of the twig, giving the branches a lushness that A. grandis lacks. The ready difference, however, and the pièce de résistance for me, is the unmistakable tangerine aroma released from broken or bruised needles.

These are a few of my favourite things. You can let me know what you think in a comment below.

Submitted by: Douglas Justice, Associate Director, Horticulture and Collections