Ground Cherry Problem
Hi and thanks for contacting Ask an Expert.
It has been very hot in the last week or so and possibly the stress on the plant has made the plant want to drop the fruits early. Was there any stress on the plant, lack of water, too much sun? The plant looks healthy now.
You stated it was one plant, could it have been sprayed with an herbicide or any chemical spray maybe early in the development of the plant.
Plants need a relatively constant supply of water. If they don’t have enough, they will wilt. Long periods of wilting, or repeated wilting, can cause stunting, pale color, and reduced flowering and fruit production. Plant roots also need oxygen. Too much water in the soil damages roots and will cause symptoms like frequent wilting, pale color, root decay, leaf dropping, and lack of vigor.
While this does not answer your question, the moisture and/or heat could be the cause. Is it all the fruits on this one plant that are doing that?
I am not finding any reasons in researching this issue other than the information noted above. It might be genetic. I have grown ground cherries for years, and never seen this issue.
It would be interesting to know if they develop fully outside the husk or drop off, turn brown or black, etc. Here is a link on growing ground cherries: https://extension.umn.edu/vegetables/growing-tomatillos-and-ground-cherries#diseases-570314 If you have any further questions, please contact us again.