Can knockout roses be cut completely back to 6-8 inches?

Question

The knock out roses I’m talking about are in a school garden. They have been in the garden quite awhile, at least 7-8 years. They are very sparse in leaves and have lots of dead wood. I don’t when they last were fed anything. I’ve been in charge of the garden for a couple of years now. I have not done anything with them. What do I need to feed them? Will rotted manure work?

Answer 1

At time of the early spring pruning, yes you can prune the knock outs down to 6 to 8 inches and they will come back fine. I recommend watering them with some water that has both a product called Super Thrive and a root stimulator mixed into it at time of first spring watering and for the next 5 or 6 times the rosebushes need watering. It helps get them going and growing well. I would feed them a good organic or organic based rose food.