| The problem with the oak leaves or any kind of covering is that during the day when the temperture goes up above freezing, they need to be able to get light on the leaves. It's hard to determine how much darkness they can stand. the leaves in the frame would be difficult to handle. The buds usually freeze when exposed to freezing temps for more than a few hours. That's why you want an early blooming type. They bloom before the temperture gets to be a problem. It's the blossums that are tender. The bush can stand a lot. However, it's worth a try. We cover ours with blankets or bedspreads that can be easily removed. What ever you do, don't allow plastic to lay against the bush. Moisture will condense on the plastic and freeze. Since you have them so close to the house, look and see if you could lean a framework of boards or PCV pipe covered with plastic against the house to form sort of a mini-greenhouse. | 
