Gabe15

If you are getting into the 40s at night, they will have to stop growing for the night. It will not hurt them, but they will not grow as fast because they will have to stop and start up again all the time. Normally, if its warm enough they will grow all night and all day. Most varieties grow normally in the 60-100°F range, anything above or below and they will slow down or stop. Some varieties (such as 'Dwarf Red') are very sensitive and may get some small amount of damage below 40°, but most varieties will simply stop growing and receive no damage.

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Growing bananas in Colorado, Washington, Hawaii since 2004. Commercial banana farmer, 200+ varieties.