Preheat oven to 400 degrees F (200 degrees C).
Arrange potatoes in a large roasting pan; nestle garlic, cut sides up, between potatoes. Dot vegetables with butter and sprinkle with rosemary. Drizzle white wine and olive oil over vegetables; season with salt and black pepper.
Bake in preheated oven until potatoes are golden and crisp and garlic is soft when squeezed, about 45 minutes.
