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Strong, healthy plants will be more resistant to diseases of all kinds, so the fight against rose disease starts at planting time. Select healthy rose plants that have sturdy-looking leaves and stems and don’t show any signs of disease or pests. Look to see if any of the leaves have black spots, red leaves, or chew marks. These are all signs of disease or infestation. Despite their name, Midnight Blue roses actually prefer sun to shade. They need about 6 hours of direct sunlight a day to be at their best, though they will still survive in very bright shade. Container rose bushes should receive a minimum of 4 hours of direct sunlight a day. The hole needs to be wide enough and deep enough to hold the roots when they're all the way spread out. Aim for a size of about 2 feet (60 cm) wide and 2 feet (60 cm) deep.  If you come across weeds or stones as you’re digging, use a garden fork to turn the soil over and remove them. Pull up anything that won't allow the roses’ roots to venture freely. If planting multiple shrubs, space them at least 2 to 3 feet (60 to 90 cm) apart to allow space for growth. Roses love soil that is enriched by manure, so incorporate some into the soil where you intend to plant your rose bush. You can purchase well-rotted manure at your local garden store.  Be sure the manure is at least 3-4 years old, since new manure can burn the roots of roses.  Try to incorporate roughly a bucket full of manure per square meter of soil. Alternatively, you can use decomposed compost instead of manure. Organic mulch should be spread over the dirt around a Midnight Blue rose bush to help retain moisture in the soil and keep weeds from growing. Apply a 2 to 3 inch (5 to 7 cm) layer, and maintain this level throughout the plant’s life. Use shredded bark mulch that has been properly processed to remove insects and diseases. Pre-packaged mulch that is sold at garden centers is the safest bet. It should state right on the bag that it has been composted or sterilized.
Pick out midnight blue roses that look healthy. Select a sunny spot. Dig a hole that will accommodate the bush’s roots. Add manure to the soil before planting your roses. Apply a layer of mulch to the area to help fight weeds.