Answer: The color change is due to unseasonably cold temperatures. Covering your ficus was a good idea; more freezing temperatures are predicted overnight for the next two days so continue to cover your ficus at night. The leaves may or may not show the signs of frost damage when the weather warms up. If they turn crispy brown, prune them off. The good thing about ficus is that it grows so fast that any frost damage will be quickly replaced when the plants begin growing in March.
Best wishes with your landscape!
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