Grow Double Delight in full sun to allow the flowers to develop a deep, rich color.
Spray the Double Delight while it is dormant with a horticultural oil spray to prevent powdery mildew. Follow the label instructions and apply at the rate recommended.
Prune the Double Delight in the spring. It blooms on new growth so early pruning will provide you with more flowers. Cut off dead canes and any scrawny stems that are smaller in diameter than a pencil. Look for branches that cross over others and prune those off as well. Double Delight is susceptible to powdery mildew, so remove as much growth from the interior of the plant as possible.
Rake the pruning debris from around the Double Delight rose, bag it and dispose of it.
Fertilize the Double Delight after pruning. Use a 15-15-15 fertilizer, at the rate listed on the package. When you see buds forming, fertilize again with a 5-7-2 fertilizer at the rate suggested on the label. Apply this formula again just before the buds open and one last time before two months before your first frost.
Spread 3 inches of organic mulch on the soil, spread out 3 inches from the main cane and 1 foot beyond the widest branches. Do this after fertilizing.
Keep the soil moist to a depth of 18 inches. Water the Double Delight at the soil, not overhead.
Protect the Double Delight rose from winter freezes by piling a 10-inch layer of compost and garden soil -- in a 2 to 1 ratio -- over the rose bush's crown and bottom branches after the first killing frost. Wrap burlap around the bush and secure it with twine. Remove the burlap and the pile of compost and soil in the spring when the danger of frost has passed.