Some tips for growing New Guinea impatiens include using high-quality potting soil that is well-drained, amending soil with compost to enrich the soil and improve drainage, planting the impatiens with access to direct morning light, and fertilizing the plant often. For outdoor plants, make sure the soil remains moist with one good weekly watering.
Before planting New Guinea impatiens, make sure the soil is rich and loose. For indoor plants, opt for a high-quality potting soil consisting of vermiculite, perlite and peat moss. For outdoor plants, till and loosen the soil before planting, and work in compost and other organic matter. The planting bed needs to have access only to morning sun with plenty of afternoon shade. Full sun all day inhibits blooming.
Water outdoor plants well once a week from soil level, and avoid soggy soil while making sure it never completely dries out between sessions. Water indoor impatiens once the soil starts to dry out. Fertilize outdoor plants once a year with a slow-release fertilizer, but fertilizer indoor plants twice a month with water-soluble fertilizer.
Each fall, trim impatiens into a rounded shape, clipping long limbs back to the nearest leaf node. Once temperatures drop below 55 F, bring the plant inside.