I would like to thank you for all your help answering my previous questions. Thank you once again. I have a new one :) I just found that Walmart usa are selling a blue rose. Please see the link below. Do you have any idea about any blue rose can be planted in Toronto weather? Walmart usa are selling the seed as per the link below. Is it going to survive in Toronto? Thank you very much.
Thank you for contacting the Toronto master gardeners regarding the blue Rosa Bush climbing rose.
Comparing hardiness zones between USA and Canada is not as simple as it sounds. The following information on hardiness zones is from one of our archived posts:
To determine zone number, Canada uses a formula that consists of 7 climate variables. Canada’s hardiness map is divided into 9 zones (from 0, which is the harshest, to 8, the mildest; sub zones (e.g., 5a or 5b) are provided for all zones except 8, which consists of 8a only). Toronto is generally considered Zone 6.
The Canadian approach is is very different from that of the US Department of Agriculture (USDA), which bases its system on average annual minimum temperatures; the USDA considers Toronto to be in Zone 5.
As well, in Canada, a hardiness zone change is afoot, with Toronto gradually moving from Zone 6a to 7a, based on updates using more recent data. For example, see Natural Resources Canada’s Plant Hardiness Zone by Municipality . Note that the “hardiness index” has changed in Toronto from 62 [1961-1990 data; this number corresponds to zone 6a] to 70 [1981-2010 data; this number corresponds to zone 7a]. See also Natural Resources Canada’s Extreme Minimum Temperature Models
It is important to be aware that, in some pockets of the GTA, the zones may be higher or lower. For example, if your garden is closer to Lake Ontario, it may be in Zone 6b or even 7. Further from the lake or in a more exposed area, your garden could be in Zone 5a or 5b. (in terms of Canadian Zones)
When selecting plants for your garden, choose those rated for more hardy zones, to maximize chances of survival. For example, if you have a plant that is hardy to Zone 5 and you live in Zone 6, the plant should be happy in your garden (as long as it receives appropriate care – e.g., sun exposure, soil type). If the plant is hardy to Zone 8, it won’t survive in your garden (although may work as an indoor plant that can survive outdoors in the summer).
Without a scientific name it is difficult to determine 100% the hardiness zone of your rose of interest. However, I did google the rose and found it available on another site where it listed the USDA hardiness zone for this rose as zone 6. Using the Canadian system, this would be equivalent to zone 7, and as a result would not be hardy in our climate.
You may want to consider checking out the Canadian Rose Society which lists roses that are hardy and easy to grow in our Canadian climate.