Care for Knock Out roses by watering them regularly, fertilizing them generously and occasionally pruning them. Mulching the roses during the winter helps them survive cold temperatures. You need water, a watering hose, fertilizer, pruning shears and mulch. Caring for Knock Out roses requires just a few minutes each week.
- Water the roses
Water Knock Out roses often during the first month after planting, keeping the soil moist. Once established, only water the roses when the top 1 inch of soil becomes dry to the touch. Do not apply water to the foliage since this can encourage disease.
- Apply fertilizer
Fertilize Knock Out roses twice in early spring with a balanced fertilizer, reapplying the fertilizer every four weeks until the middle of August.
- Prune selectively
Trim out any dead wood at the end of each winter. Shape the bush, opening up the center by removing any crossing branches. Follow the natural lines of the bush, trimming the branches back to one-third to one-half of their original lengths to maintain the best shape.
- Mulch in the winter
Apply straw to the base of the plant to protect it from severe winter temperatures. Remove the straw from the plant as soon as temperatures warm up.