Answer: Based on your description, your planting spot sounds like an ideal one for the New Guinea Impatiens, so I wonder if perhaps one or maybe two things happened. One is that by so carefully keeping the plants under lights they were not fully conditioned for outdoor life when they were planted, and the second is that the ground may not have been quite warm enough when they were set out. These plants prefer a warm soil that is rich and moist yet well drained, and they really resent those nippy cool nights that can occur early in the season. Next time you might want to try hardening them off or conditioning them a bit for a week or so to gradually accustom them to outdoor conditions, especially if the weather is still a bit unsettled, and try giving them some protection at night as a precaution early in the season.
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