There is a mod that lets you put nearly anything on an item stand and more options for armor stands.
In the future there may be updates that let you put more on them in vanilla....but i wouldn't count on too many.
I recently read that we will be able to finally put turnips on item stands. It was/is the only veg/meat/berry that you could not place on an item stand. The dev said that it must have been overlooked lol.