Q.Knockout Roses Spring Start
The winter here was warmer than general with less overall snow but still ~40 in. A very warm Feb, with some melting. As of June 1st they are showing little sign of life, (leaves and greening canes). With some more severe pruning and feeding is there some hope they will come back yet? Only 1 plant of 10 has actual leaves.
Maybe. Water them with some water that has both a product called Super Thrive and a Root Stimulator in the same water. Do this the next 5 to 6 times they need watering. Also sprinkle 1/3 cup of Epsom Salts around the base of the rosebushes, work lightly into the soils and water in. It is okay to use the same water mix above to water it in.