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How to Care for Knockout Roses


Nature has produced many beautiful plants and now science has too. Botanists recently created the hybrid flower named the Knockout rose that is not only exquisite, but is also disease resistant and easy to grow in a variety of soils and climates [source: Krismers]. Read the tips listed below and accent your garden with lush Knockout roses.

  • Knockout roses can thrive in a wide range of soils. They can survive and grow in dry climates, but they prefer moist soil with good drainage. These roses flourish in soil with a pH of 6.0 to 6.5. Test your soil with a home kit. If the pH level is too high, add sulfur or pine needles to the soil. If the pH is too low, add some lime juice [source: Martin].
  • Knockout roses can be planted virtually throughout the year. However, it's best to avoid planting in extreme weather conditions, including winter and the hot summer months. Plant the rosebush in an area with good air circulation and at least six hours of daily sunlight. The more sunlight, the more the plant will thrive. Knockout roses bloom in spring and continue to produce flowers until the first frost [source: Krismers].
  • Knockout rosebushes are self-cleaning, so you don't have to pick out dead flowers.
  • Knockout rosebushes only need pruning once every three years. Toward the end of winter, use sharp pruning shears to cut the plant down to 12 to 18 inches (30 to 46 centimeters) to encourage growth in the early spring [source: Martin].
  • Knockout roses are incredibly disease resistant and can stand up to mildew and aphids. Watch your bush if it gets infected with black spots. If the infestation gets out of hand, spray the bush with fungicide [source: Botanical Journeys].

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