My impatiens suddenly wither within 3 days. I think something is eating them, but I have not actually had a chance to scratch around and see. If snails as I suspect, what can I do about it? Or if it's something else, is there a general way that would help?
Certified GKH Gardening Expert
It sounds like there may be a root rot or a bacterial wilt to blame. This article will help: https://www.gardeningknowhow.com/ornamental/flowers/impatiens/impatiens-problems.htm
If snails or slugs are a concern, these articles will help: https://www.gardeningknowhow.com/plant-problems/pests/organic-snail-control-how-to-control-garden-snails.htm
Impatiens walleriana are being plagued by a 'new' disease called "impatiens downy mildew". The following article should be helpful: http://www.mnn.com/your-home/organic-farming-gardening/stories/impatiens-disease-becomes-hot-topic
This article is a pdf from an industry giant in the horticultural industry:
Reputable growers should be suggesting that consumers substitute begonias, New Guinea Impatiens or petunias for impatiens walleriana.