Plant the rose hybrid impatiens where it will be protected from the hot afternoon sun. Impatiens does best in filtered or partial shade.
Maintain consistently moist soil for your rose hybrid impatiens. Deep-water the impatiens at least once a week, providing enough irrigation to soak the soil to a depth of 4 to 6 inches. Water your hybrid impatiens whenever the surface of the surrounding soil feels slightly dry to the touch.
Fertilize rose hybrid impatiens once a week during the growing season with a half-strength solution of a balanced, water-soluble fertilizer. Use the fertilizer product according to package directions to avoid burning the roots of your flowers.
Prune back your rose hybrid impatiens a bit when they reach approximately 6 inches tall. Pinch off the new growth at the ends of the plant to encourage it to branch out.
Monitor rose hybrid impatiens for problems with common insect pests such as spider mites, aphids and thrips. Rinse affected impatiens with water from a garden hose to wash away some of the pests.