Arboretum

The Lilac Dell exhibits over 400 species and cultivars of common lilacs. French hybrids form the basis of the collection, but also displayed are Preston hybrids (originated in Canada by Isabella Preston), early-bloomers such as hyacinth lilacs and a selection of species found in the wild. An introductory Lilac Walk at the entrance to the Lilac Dell is organized in a series of exhibits that interpret the desirable breeding characteristics of lilacs, and major developments in the history of lilac breeding. On more challenging terrain, The Katie Osborne Lilac Collection within the Lilac Dell is one of the most diverse and one of the definitive collections to demonstrate the range of the genus Syringa. A popular seasonal attraction, it provides visitors with weeks of delightful springtime colour and fragrance.

Magnolias are among the most primitive of flowering plants, with fossil remains dating back over 100 million years. Relatively unchanged since then, they are found in the wild in tropical and temperate Asia and America. The collection, located in two separate areas of the Arboretum, displays a selection of magnolias that are hardy in our area. The collection also exhibits Ontario’s native magnolia, the Cucumber-Tree (Magnolia acuminata), an endangered species found wild in only a few locations in the Carolinian Zone. The western section of the collection was originally developed as a memorial to local architect Lester Husband, while the eastern section, near the Synoptic Shrub Collection, commemorates past Gardens’ staff member R. A. Sims.

RBG’s woodlands are home to some species more commonly found in the southern United States. For example, south of the lilac dell the collection of dogwoods (mostly Cornus florida and its cultivars) and redbuds (Cercis canadensis) at the edge of this woodland provide a springtime show of mauve-pink and white blossoms. A member of the Pea family, Redbud reaches the natural limits of its range near Lake Erie, though it can be planted further north. Interestingly, Cornus are commonly used as shrubs in the landscape but can reach 5m tall in their natural habitat.

Our display highlights the range of form and colour in the Malus genus. Crabapples are a common small tree used in residential landscapes. Over the years RBG has grown and evaluated many of the hundreds of cultivars bred from the two-dozen or so wild species found in North America, Europe and Asia.

At RBG, our flowering cherries are part of our early spring celebrations. Globally, flowering cherry trees have a long history, especially in Japan where cherry blossoms are celebrated, and flowering times recorded dating back 1300 years. RBG also annually records the flowering times of its Cherries as part of a biological science known as phenology which is an important tool in helping to track climate change. In 2010, we added 34 trees to this collection, donated to RBG as part of the Sakura Project. These trees are planted at both the Arboretum and Rock Garden sites and are a must see in early spring.

The Synoptic Shrub Collection presents a living encyclopedia of shrubs that can be grown in our area. Like a dictionary, it is organized alphabetically, by genus, from A to Z. It includes species as well as cultivated plants commonly available in the horticultural trade as well as unusual shrubs that are harder to find and have been sourced from other botanical gardens through plant exchanges. Currently undergoing rejuvenation, visitors will be able to see how a collection of mature shrubs can be revitalized.

Also called evergreens, needle-leaved trees or softwoods, conifers are trees whose seeds are open to the air, most often in cones. Most keep their leaves for at least two years, and all have soft resinous wood.

Ontario’s tree emblem reflects the major role that some members of this group of plants have had on our history—the British Navy’s demand for Eatern White Pine (Pinus strobus) shaped the early settlement of our province. Along with pines, spruce, and firs the Pinetum explores the diversity of conifer genera around the world and features 140 unique types represented by over 200 individuals.

Native plants provided Indigenous peoples with almost all of life’s essentials. Starting in the Arboretum near the Nature Interpretive Centre, this new trail explores plants used by the Anishinaabe peoples, and their connections to culture, language, ecology and history.