Somewhere I read that a Yorkie isn't fully mature till 3 years of age, at which time the coat may reach the floor.
Mine rolls on carpet, in leaves, hardwood floors, in the bed, never wrapped, and I just trimmed about an inch or two off his coat...he was tripping over it. But he's 13 years old...
Good, quality food, coconut oil, wild Alaskan Salmon oil, and glucosamine supp for his joints and CT.... made his nails grow quicker too.