The verdant exuberance of June foliage is sometimes difficult to equal with flowers, but there are a number of ornamentals that manage the task. Among the commoner June flowers, roses and weigelas and earlier perennials such as geraniums and much of the daisy clan come to mind. In the Botanical Garden there are these, as well as a few less obvious examples that are worth looking out for.
Members of the Styracaceae (snowbell family) are very popular when in flower, as they mostly have attractively drooping, white, bell-shaped blooms that are strongly lemon scented. Nearly all of the genera other than Styrax flower in April or May, but the ten or so species of Styraxpresent in the Garden all produce their flowers in June. One of the most beautiful is a Chinese selection of the Japanese snowbell, known as S. japonicus ‘Fargesii’, which has neat, crisply white bells, each backed by small purple-green calyx. The flowers are borne on long, slender similarly dark stalks, and they festoon the undersides of the wide, horizontal branches in incredible numbers. This tree is visible at the corner of Stearn and Rehder Trails.
As a group, magnolias need little introduction, but the species most celebrated at UBC are the precocious-flowering types (i.e., flowering before leaf emergence). By June, however, the excitement over those earlier voluptuous (and voluminous) blooms has mostly passed. June-flowering magnolias are primarily the evergreens, and most of these are poorly known in gardens. Other than the North American species, all of the cold-hardy evergreens are from China and have only been in western cultivation for a few years. Among the most outstanding Asian species in terms of flowers are M. insignis (corner of Maack and Henry Trails), M. chevalieri (on Decaisne near Forrest Trail) and M. conifera (off Ludlow Trail). Note that there is a Botanical Garden Magnolia (smart-phone) Tour, which discusses these species at length (look for the distinctive dark blue engraved signs).
Another important group of June-flowering trees is Stewartia. There are five Stewartia species at UBC Botanical Garden—one from eastern North America and the others from Asia. Most mature stewartias can usually be differentiated on the basis of their distinctive bark, but the flowers are certainly worth admiring. All have creamy white, five- to six-petaled flowers with a prominent central boss of stamens, the petals with distinctively crinkled edges. The largest flowers belong to Japanese stewartia, S. pseudocamellia, which is also the best known, but mostly for its spectacular exfoliating bark (Upper Asian Way at the Moon gate). Perhaps the most floriferous of all stewartias is S. rostrata (beaked stewartia), a Chinese species (Lower Asian Way near Soulie Trail). Before opening, the abundantly produced flower buds are conspicuously enfolded by twisted leafy wrappers, and as they open, the flowers are rimmed bright pink before eventually fading to pure white.
Submitted by Douglas Justice, Associate Director, Horticulture & Collections, May 31, 2014.