How can you make a bonsai tree grow a bigger trunk ?
that defeats the purpose
Put it in a bigger pot and uses A LOT of feed for it and over time It will grow bigger
The trunks can grow wider, but not taller. They get wider as they age, not really anything you can do to make them wider. Here is a link with a ton of info regarding how to care for the wee little trees.http://www.bonsaiempire.com/care/blog