Roses add an unmistakable beauty and fragrance to the home garden but require routine care to retain their beauty. Rose bushes that are under stress from improper care are more susceptible to disease. Watering practices, routine fungicidal spraying, winter protection and nutrition all play a role in the overall hardiness of roses. Give special attention to these details and your roses will thrive.
Keep in mind that overhead watering in the early spring before growth appears will keep the canes of the rose bush hydrated. After growth appears, water only at the base of the plant and early enough in the day for any wet leaves to dry. Wet foliage can lead to disease. Apply an inch of water per week.
Testing the pH level of soil before fertilizing roses is necessary. Roses need a soil pH range of 5 and 7.5 Low soil pH levels can be corrected by applying lime. If the soil pH range is higher than 7, lower the pH level with applications of sulfur.
Adding organic matter to the rose bush bed will ensure better drainage and provide nitrogen to the soil. Well-rotted barnyard manure should be applied in early spring, according to Mervin C. Eisel and Mary H. Meyer at the University of Minnesota Extension. Soybean and bonemeal are also appropriate organic fertilizers for rose bushes. In addition to organic matter, fertilize with a well-balanced 10-10-10 fertilizer once monthly until the beginning of August. Follow fertilizer recommendations for application amounts.
Planting disease-resistant varieties of roses will provide some protection against disease. Rose bushes may still become diseased, but will be better able to survive them. Roses are prone to fungal diseases, such as powdery mildew, black spot and rust. Fungicides for the treatment of powdery mildew include Triadimefon, Propiconazole, Triforine Thiophanate-methyl and sulfur. Black spot is treated with Captan, Folpet, Mancozeb and Triforine. Rust treatments are Mancozeb, Triforine and Chlorothalonil.
Routine preventive spraying with fungicide is recommended. Spray all foliage surfaces and follow dosing instructions, according to Stephen Nameth and Jim Chatfield at the Ohio State University Extension.
Safeguarding roses against cold temperatures and frost is essential. Creating a mound of soil around the base of the rose bush canes after the first frost will insulate the plant and protect it from injury. For wind protection, tie the canes together or prune slightly to avoid movement that could shift the mound of soil around the base of the plant. When the ground has completely frozen, pile 8inches of straw, hay, leaves or another mulch on top of the mound, suggests the University of Nebraska-Lincoln Extension.
For climbing roses with long canes, anchor the canes to the ground and cover them with mulch until all danger of frost has passed.