Question
My son lives in the Toronto, Ontario area of Canada and wants to put flowering vines in cedar boxes on his deck. We were wondering which perennial would be the best for that area and how do we treat them

Answer
Make sure your plants will get enough Sun for the plants you choose.  Flowering plants won't flower if there's too much shade and they are full Sun plants.

You should be aware that it will be very important to move these Cedar Boxes to a protected location.  They are too shallow to keep the roots of anything growing in them from freezing solid.  Even the hardiest perennials don't have freeze-proof roots.

I would therefore recommend you consider instead the option of hardy Annuals -- hardy so that you can enjoy them longer, Annuals because you won't be dealing with the perennial problem of winterizing the boxes and protecting the plants all Winter.

In addition, most perennial plants are not THAT perennial.  Vines, shrubs, flowering plants -- they never seem to last long enough, and none last forever.

One last selling point for Annuals:  Their flowering season.  It's long -- Summer-long, in fact.  While perennials usually start earlier, they end just as Annuals are taking over for the rest of the Summer.

That said, although as a New Yorker I have all kinds of opinions on what you should love and hate, I will control myself here and refer you instead to the Bluestone Perennials website, where you will find a computerized 'Custom Plant Search' on the left side of the page that will give you many dozens of choices of Vines:

www.bluestoneperennials.com

Since you asked, I am partial to Moonflower for its evening scent and Heavenly Blue Morning Glory for its breakfast blue.  They are great together.

Of perennials, Clematis is very easy and some bloom all Summer.

Thanks for writing.

THE LONG ISLAND GARDENER