My wife and I planted 16 Rose bushes with 5 different varieties. We also have different types of shrubs. I was told to put mulch around the rose bush base up to about 10 inches.
I also have a product called Wilt stop. This is to protect the Roses and some shrubs from drying out in the winter. Can I put that on now or do I have to wait yet. I know you have to put it on when the weather is above freezing.
Thank you for contacting Toronto Master Gardeners.
It sounds like you have created a beautiful rose garden.
Most winter damage to plants comes from the freeze thaw temperature changes. That is where burying your rose bushes will help protect them. I have attached one of our articles below that goes into the details of exactly how to protect and bury the roses during the winter.
You mention shrubs as well. Shrubs are not usually buried and it is important to keep the woody trucks clear of mulch so the wood does not get damp and breakdown. Shrubs should be mulched with a doughnut of mulch to protect the roots and limit temperature changes to them.
You do not mention if the shrubs are deciduous or evergreen. Deciduous shrubs do not have many issues with drying out over the winter as they have no leaves but evergreens can as the needles continue photosynthesizing in the winter sun. Having sufficient moisture during the fall, before the ground freezes, is key to avoiding needle desiccation. I have read mixed reviews and advice on the value of using the product you mention. The best way to apply it is to follow the directions with the packaging as that should give you an idea when is the best time and best way to apply the product.
At the end of the day, overwintering is very dependant on the type of winter we have, how much freeze thaw we experience and how much snow cover there is to protect the plants. We have seen so many different types of winters here in Ontario. The best you can do is plan for the worst and hope for the best.