Eastern Redbud or other flowering tree?

(Question)

Hello!
I am on the landscaping committee for a condo in downtown Toronto, and the Board is looking into planting 2 – 3 ornamental trees as part of a rejuvenation project. They have considered flowering cherries to start, but I have come across the Eastern Redbud (Cercis Canadensis), which seems like a hardier flowering tree?

Given the conditions below – do you agree, or do you think that there are better options from which to choose?

Here are some details:
Zone? I’m not sure what zone this is. Toronto has cold winters and hot summers…

Garden Light Conditions: Our building has a large back garden, with a number of tall/mature deciduous as well as large coniferous trees, which throw some shade. The garden bed that I am working with is also located on the southern most portion of the garden, along a back fence (not a solid fence, so it allow light), with a building close by to the south. However, the large trees (described above) are to the west, which would cast afternoon shade more than this southern-neighbour building. I would say that the location gets only partial (not full) sun for these reasons.

I’ve included a map and the trees would be planted in garden where two previous trees were blown over in a storm. You will see what other things are growing there too, with this map.

Soil: Our garden is directly over a subway line, so there is about 3-4 feet of alkaline soil, then there is concrete below that. The soil is more clay-like than sandy. We apply mulch and fertilizer (both flower bed, and tree-stake fertilizer) on a rotating cycle every 2 (fertilizer) to 3 (mulch) years. We have an irrigation system, with sprinklers (not drip-line) along this southern garden bed.

I would really appreciate your help. I am trying to make the best choice for an ornamental tree, and so far, the Eastern Redbud is a front-runner…

(Answer)

Thank you for contacting the Toronto Master Gardeners with your inquiry concerning the planting of Eastern Redbud trees.

Eastern Redbud, Cercis canadensiscan be grown successfully in zones 5-9 so it will grow in Toronto’s zone 6. These trees are tolerant of a wide range of soil types and frequently appear on plant lists for especially tough sites.They can adapt to many types of soil, including alkaline clay soil as long as the soil is not prone to flooding or bogginess. Full sun and partial shade are best for this tree, meaning it prefers a minimum of four hours of direct, unfiltered sunlight each day. These trees will benefit from a yearly application of compost. You never mention in your description if your planting site is well drained. If drainage is not an issue then this tree will be a welcome addition to your landscape. The folling website gives additional information on this beautiful specimen tree: http://hort.ufl.edu/database/documents/pdf/tree_fact_sheets/cercanc.pdf

Another tree you might like to consider is Serviceberry, (Amelanchier canadensis). This plant can be found as a tree or multi-stemmed shrub. Serviceberry provides year round interest producing white flowers in spring, blue-black fruit in summer, and brilliant fall foliage. Serviceberry will tolerate wet sites and flowers and fruit best in full sun, but is tolerante of some shade. https://wimastergardener.org/article/serviceberry-amalanchier-spp/

An excellent non profit resource for  advice, sourcing, planting  and information on trees grown here in Toronto is LEAF https://www.yourleaf.org/.