Oh first time gardening can be maddening! :shock: LOL
But don't give up, you live and learn as you go. It is though very upsetting when a costly perrienal dies!
I like hosta's they seem to be able to grow no problem.
Check the garden listing of your local kijiji to see if anyone in your area is selling plants. I also have seen ads in the newspaper for some local nurseries and their sales.
Oh and check this gardening forum they have a Canadian plant and seed exchange page!
http://forums.gardenweb.com/forums/excan/
It also depends on where you are planting, ie what type of conditions, sun, shady, etc. As well as your level of expertise.
Find a reputable nursery or garden centre and then ask them what they recommend for your house and how much time you want to spend on maintaining.
Home depot and other such stores, staff won't be able to provide you with that good information.
I have had luck with peonys, hydrangeas, spirea, lilies, iris, hostas, phlox, yarrow. All of these plants can get quite big, except for the phlox. You may need to use other plants depending on your region.
I have been told that bleeding hearts, thrive in most conditions and that you can't really kill it. Well I have tried and tried to grow those things and can't! I finally gave up, then my son bought my one for mothers day, so here we go again.
Hope this helps some.