Fig trees can take 20-25 degree F temperatures depending on the variety but when you get into consecutive days of of sub 20 degree temperatures the fig branches often freeze through and die. You want to protect them so you get figs the following year. If you don't protect them you often get new growth/branches that come up from the roots/ground but don't have enough time to produce the inverted flowers or fruit. You want to wrap you fig tree with 3 layers in Maryland Zone 7.
Good Luck with Your Garden,
Gary (The Rusted Garden)
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