I am sorry for this delayed reply to your gardening question. The spring rush has brought a deluge of questions and we are working hard to catch up!
Based on how quickly your foxgloves appeared to turn brown I would think they suffered a pretty major root problem. Either drought or soggy wet soil conditions can result in plant death. So can burn from a pesticide or damage from a weed and feed fertilizer.
Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon!
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