How u make the texture model for plant a block texture and not a cross model?

What do you mean? It already should be a block it self.

I think OP means how if you make a plant, when it is broke up and or in your inventory, it will still be a completely flat crossed texture unlike ordinary saplings which are a (minecraft) pixel thick.

Oh. Well in that case.. Im too sleepy to answer it correctly so excpect me here tommorow :p

'expect me here tomorrow'

Well.. I am here :/ I just can't help him cuz I dont jave enough info. But if can give it to me somehow Ill try my best to help.