butternut squash

Question

The skin of some of my butternut squashes has turned brown, in ring patterns. The fruits are still very firm. What has caused this, and what should I do in future to stop it, please?

Answer 1

This could be black rot, also known as gummy stem blight. This disease affects both the fruit and stems/leaves Anthracnose is another possibility. Both are common diseases in some regions.

See these articles for more information:

http://vegetablemdonline.ppath.cornell.edu/factsheets/Cucurbit_FrtRots.htm

https://www.gardeningknowhow.com/edible/vegetables/squash/squash-pumpkin-rot-disease.htm

https://ag.umass.edu/fact-sheets/cucurbits-black-rot