Impatiens hawkeri, commonly called New Guinea impatiens, is notorious for its sun intolerance, needing the full protection of trees or other casters of shade. This doesn’t keep it from being an extremely popular bedding plant in the U.S., thanks to how it can flower non-stop from May to October. Despite its haste to scorch in the afternoon sun, New Guinea impatiens can develop mottled foliage due to low light or low soil fertility. Overwatering can cause leaf and flower bud abscission.
In one of Horticulture’s Smart Gardening Workshops, Dr. Allan Armitage shared the tip that you can allow the plants to wilt before watering them for the first few weeks after planting. This will make them able to withstand dry spells later. If you still have problems growing New Guinea impatiens or you can’t provide shade, try plants from the Sunpatiens series, which are bred to withstand the sun.
All New Guinea impatiens are not susceptible to impatiens downy mildew, a disease that has wreaked havoc on bedding impaiens (I. walleriana) in recent years.
Image: Forest & Kim Starr
Find more plants that can thrive in the shade plus design tips and advice for coping with shade-related problems in Horticulture’s Gardening in the Shade CD.
Take a gardening class from the comfort of your own home, on your own schedule. Try Garden How-To University’s Shade Gardening class, a slide show and audio that you can download.