Our deer typically don’t hit the tubers with gusto until the forage is gone. They hit the forage as soon as it’s more than a few inches high. They don’t wait for the frost. I will say it took a couple years for the deer to discover brassicas. Once they learned about, they can’t leave it alone. I think brassicas are unrivaled in tonnage and attraction on our place. I’ve planted beets with them and never observed a difference in attraction.