Dividing Hydrangea is very easy. Just cut the plant from anywhere and start a new plant. Cutting is only needed when you have to move the plant but anyway it breaks down in the moving process.
How Do I Divide A Hydrangea Plant?
Yep, it's very easy to propagate. It's all about the PH with that one. Putting coffee grounds in the soil mix will make them the prettiest shade of blue you could ever have...