I want to consider Sedum album ‘Coral Carpet’ as a ground cover. My questions
1) Can they survive Toronto winter. I know the zone is saying in the label 2-9 but I do not believe these marketing labels
2) Is it better choice than Thyme or veronica liwanensis, in term of Hardiness (surviving winter). My yard is sunny but lets say 85% sunny.
Thank you so much for all your help
JThank you for your question to the Toronto Master Gardeners.
I have loads of experience with Sedum but not this particular variety, so I looked on the websites of what I consider the most reputable plant growers and distributors, as well as botanical gardens and the University of Guelph.
Sedum album ‘Coral Carpet’ seems perfect for your Toronto garden. We are in Zone 6 (or Zone 5 if you use the USDA guidelines) I found this plant’s hardiness rated on one site as ideal for as cold as Zone 2 but would tend to believe a warmer estimate of Zone 4 at another site. This means your investment of plants is likely to survive! One thing you can do to reduce the number of plants you need to purchase is to split each container in half and then space your plantings slightly farther apart than recommended. From my experience with low growing Sedum, they spread easily and rapidly. I applaud your decision to use groundcover instead of costly and environmentally unfriendly grass. Sedum album ‘Coral Carpet’ will suppress weeds and require almost no maintenance. Just be sure it receives regular watering.
My only concern was whether it could withstand the impact of people walking on it, as they would a grass lawn….and yes, it can! Light foot traffic is fine.
I have found Thyme to be slow growing but also beautiful. You would need to research carefully the varieties you are considering as some may not be winter hardy. Sedum would require less care.
Finally, you asked about Veronica liwanensis (Turkish Speedwell). Here is a link to a previous question we answered about the same groundcover:
On this page you will find the following links for more research:
I hope this helps you make a decision. Good luck.