begonia tubers

3 years ago I bought some lovely begonia plug plants from QVC. I've manged to keep most of them going and the tubers are now starting to sprout again. However, some of them are absolutely huge; can I split them to make more plants and if so what is the correct method?

 

Yep , ok to split provided there's shoots on each part.I just make a clean cut then dust the cut edge with Flowers of Sulphur,i started off with just a few & now have loads.