Our eastern neighbour just removed a large (100ft?) Siberian Elm, shifting our yard from being mostly dappled shade to full sun. We are missing the height interest and wildlife. Our yard is very narrow (approx 14 feet wide) and covered with decking so sadly it is not really feasible to plant our own tree in the ground. Do you have suggestions of trees that would grow in containers? Ideally they would be fast growing and native. If they could be columnar (or at least had few low branches or could be pruned that way) that would also suit well. Suggestions for containers would also be appreciated— half barrels are the largest I have found but if there are larger/lighter ones it would likely be good to be able to move the tree around. I know this is very particular — thanks so much for your thoughts and help!
Thank you for contacting Toronto Master Gardeners.
Our website has information on growing in containers: Toronto Master Gardeners Guide: Container Gardening
Planting an evergreen or deciduous native tree whichever you decide to place in a planter; Our guides will provide information on how to successfully grow in a pot. Please follow the instructions in our guides on size of pot, drainage, type of soils, and fertilizers. It provides details of the type of conditions that may affect the life of the tree for example, thaw and freeze in a container. How to overwinter the containers with plants.
Missouri Botanical Gardens has information on growing native plants in containers. Missouri Botanical Gardening Container Gardening Evergreen
The Master Gardener guide also suggests the type of evergreens that would overwinter in a container, Chamaecyparis or False Cypress for its hardiness zone. Taylor’s juniper a fast growing columnar form a cultivar of Juniperus virginiana, and eastern red cedar. Taylor Juniper
Smaller trees in containers are best, the roots do not grow around in the container which could strangle the tree. Smaller deciduous trees even though they are not columnar can be pruned to size and kept to a scale you desire. Deciduous small native trees such as American smoke tree Cotinus obovatus, Allegheny serviceberry Amelanchier laevis, American bladdernut Staphylea trifolia, Canada plum (Prunus nigra), Cornus florida or flowering dogwood.
This website allows you to choose different sizes of trees and provides details of size and some requirements: Tree Canada Resources and the Morton Arboretum
Happy Gardening