Failure at Overwintering rose cuttings
Hello everyone,I am deeply dismayed,last fall I put away over 400 well rooted cuttings in one gallon pots.I placed them underneath our deck so they wouldn't get a heavy snow load on top of the mulch and break the canes(which is what happened the previous winter).I placed snow fence around the deck,then filled the area with leaves to protect the roses from the cold.The results-probably half or more of the roses are dead.
Question 1-should I have used straw instead of leaves?
Question 2-should I maybe be burying them below ground(pulling them out of their pots and burying them bareroot)?
Question 3-should I try overwintering them in my unheated hoophouse?I am afraid of it getting warm and them breaking dormancy on a sunny day in winter?
The temperatures here can get to -40, and I know if I were to keep them in the basement,it is warm enough they wouldn't go dormant and the spider mites,aphids would have a feast.
Thanks in advance for your help,it is a long way from winter again,but i need toi come up with a method that doesn't cause me to lose 50% or more of my cuttings.