Answer: Yellowing leaves this time of year isn't all that unusual for potato vines. They are responding to cooler nighttime temperatures and lower sunlight levels. I'd recommend cutting the vines back to encourage healthy new growth. You can cut them back now or wait until spring. If you leave them alone now, they may develop new leaves to replace those that were lost. If not, you can cut the stems down in the spring to prompt the development of healthy new growth. Fertilize in the spring with a liquid 20-20-20 (diluted to package recommendations) to help keep the plants a healthy green all growing season.
Best wishes with your potato vines!
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