See the Arboretum Collection Map Virtual Tours: Tour Arborteum. Plant collections: Katie Osborne Lilac (Syringa) Collection Magnolia Collections Ontario Native Trees and Shrubs Hedge Demonstration Dogwood (Cornus) and Redbud (Cercis) Collection The Maze Synoptic Collection of Shrubs Weeping Tree Collection Rhododendron and Azalea (and other acid loving plants) Collection The Pinetum—Conifer Collection Native Plants Hawthorn (Crataegus) Collection Forsythia Collection Crabapple (Malus) Collection Avenues of Trees Beech (Fagus) Collection Katie Osborne Lilac (Syringa) Collection (Lilac Dell and Lilac Walk) Peak interest: May and early June The Gardens is home to the largest lilac collection in the world. It also is the home of the International Registration Authority for new lilac cultivars, and a site for their display and evaluation. From the 26 wild lilac species native to eastern Asia and southern Europe, breeders have developed over 1,600 cultivated varieties. An introductory Lilac Walk at the entrance to the Lilac Dell is organized in a series of exhibit that interpret the types and characteristics of lilacs, and major developments in the history of lilac breeding. The Lilac Dell exhibits over 800 species and cultivars of common lilacs, French hybrids, Preston hybrids (originated in Canada by Isabella Preston), early-bloomers and wild species. Depending on weather, peak bloom in late May is a breathtaking spectacle of scent and colour. Visit during the Lilac Festival and enjoy special tours, demonstrations and live music. The Lilac Dell was originally developed through a generous memorial donation by the family of Hamilton lilac enthusiast Katie Osborne. Back to Top Magnolia Collections Peak interest: April and May Magnolias are among the most primitive of flowering plants, with fossil remains dating from over 100 million years ago. Relatively unchanged since then, they are found in the wild in tropical and temperate Asia and America. The collection, located in two separate locations in 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. Back to Top Ontario Native Trees and Shrubs Peak interest: all year The Gardens lies near the northern limits of the Carolinian Life Zone (Deciduous Forest Region), Canada's most threatened life zone. Hickory, sassafras and walnut give our forests a distinctly southern flavour. Along with these southern trees you'll find maple, beech and hemlock—species characteristic of the more northerly Great Lakes-St. Lawrence Forest Region. Wander along a woodland trail and explore our collection, which includes over 70 of the 90 species of trees native to Ontario. Some have grown here naturally, others have been planted. Ontario-native shrubs and vines also have been labelled. This collection was established in 1972 through the generosity of the late W.A.T. Gilmour, Hamilton businessman and naturalist. Back to Top Hedge Demonstration Peak interest: all year In addition to cedar, privet and other traditional hedge plants, this demonstration collection features species less commonly used, including white pine (Pinus strobus) and purple-leaved sand cherry (Prunus x cistena). Back to Top Dogwood (Cornus) and Redbud (Cercis) Collection Peak interest: May Our native flowering dogwood (Cornus florida) and its cultivars are the focus of this collection, adjacent to a display of redbuds (Cercis canadensis). A member of the Pea Family, redbud reaches the natural limits of its range near Lake Erie, though it can be planted further north. Back to Top The Maze Peak interest: all year Mazes have been a source of frustration and delight for at least 4,000 years. All around the world, various cultures have used them for defense, ritual, amusement and as traditional garden elements. Almost 300 white cedars (Thuja occidentalis) have been used in our maze. Twenty white cedar cultivars make up a design of four concentric circles, allowing you to contrast their colour and texture. The maze was developed with the financial assistance of the Hamilton Spectator. Back to Top Synoptic Collection of Shrubs Peak interest: all year This collection is an overview of shrubs that can be grown in our area. Like a dictionary, it is organized alphabetically, by genus, from Acer palmatum (Japanese maple) to Zanthoxylem simulans (Chinese prickly ash). A 300-metre-long paved path winds through the collection, making it fully accessible. Back to Top Weeping Tree Collection Peak interest: all year The Arboretum provides a great opportunity to compare and contrast the characteristic shapes of tree species. While some trees weep naturally, others are bred for that shape. Many of the cultivars we display originally came from selected upright parent trees with an abnormal growth form. Others are grafts, where a low-spreading plant has been elevated to tree status, by joining it to the trunk of an upright form of the same species. Back to Top Rhododendron and Azalea (and other acid soil-loving plants) Collection Peak interest: June While this collection displays only a fraction of the almost 1,000 species and countless cultivars of Rhododendron, it features many cultivars that are reliably winter hardy in this area. Some of the rhododendrons planted here have thrived in this location for years. This site was modified to provide these acid-soil-loving plants a moist, well-drained, acid, organic soil, and overhead shade (oak trees) and protection from the winter winds (spruce trees). The genus Rhododendron also includes azaleas, which are displayed at the Rock Garden. A complimentary Rhododendron Collection is located in the Woodland Garden in Hendrie Park near RBG Centre. The arboretum collection was developed with the assistance of rhododendron expert Dr. E. Frank Palmer, a former Director of the Ontario Horticultural Research Station. Back to Top The Pinetum—Conifer Collection Peak interest: all year 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 white pine (Pinus strobus) shaped the early settlement of our province. Along with pines, our collection explores the species and cultivars of many conifer genera from around the world. Back to Top Native Plants Peak interest: all year Tundra, prairie, boreal and deciduous forest, together these landscapes make up Ontario, and provide habitat for over 3,000 plant species. At the northern limit of the Carolinian Zone, the Gardens is home to over 1,000 species of plants, many of which have a distinctly southern flavour. A small selection is displayed behind the Nature Centre and labelled for use as a living field guide to local wildflowers. Back to Top Hawthorn (Crataegus) Collection Peak interest: all year These members of the rose family thrive on open land, where their dense, thorny growth provides shelter for wildlife. Along with interesting form, their glossy leaves, white to pink flower clusters and bright red haws (fruit) make them attractive garden shrubs/trees year-round. Our collection focuses on wild hawthorn species from across the northern hemisphere. Back to Top Forsythia Collection Peak interest: April/May This collection is planted around the Arboretum parking area, and includes hybrids and cultivars of Forsythia, which are exceptionally hardy in our area and suitable for cultivation further north or in exposed locations. Back to Top Crabapple (Malus) Collection Peak interest: May (flowers) and fall (fruit) Our collection samples the astounding diversity of crabapples. We have 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. Back to Top Avenues of Trees Peak interest: all year In the open, sunny spaces of the Arboretum, trees grow freely into their natural shapes. Many of the trees are displayed in themed avenues that radiate out from the central parking circle. Themes include large boulevard trees, conical-shaped trees, globe-shaped trees, medium-size oval-headed trees, fastigiate (upright) trees and small-size flowering trees. Many of the avenues end in a circle of trees of one species or cultivar. By far the most spectacular is the tulip tree (Liriodendron tulipifera) circle near the shrub collection. Back to Top Beech (Fagus) Collection Peak interest: all year Beech trees are treasured for their stately appearance, smooth grey bark, glossy leaves, slow growth and enormous size. This collection features both the European beech (Fagus sylvatica) and its cultivars, and the American beech (Fagus grandifolia). Included are beech cultivars that have columnar or weeping forms, or various leaf colours including green, yellow, purple and pink. Individual trees have been planted with enough space to allow them to exhibit their natural form at maturity. Back to Top RBG Centre Laking Garden Rose Garden Rock Garden What’s in bloom See the best blooms of the season. Ask about a plant in our collections E-mail us a question about plants in our collections. Ask a gardening question E-mail your gardening question to the Gardening Information Desk. Information resources Learn about our Library, Herbarium and Geographic Information System. Directions Click here to see how easy we are to find.
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