可以有三种填法：
Which kinds of vegetable grows well (good) in your hometown? 在你们家乡哪些种类的蔬菜长得好？
Which kinds of vegetable grows better (good) in your hometown?在你们家乡哪些种类的蔬菜长得更好？
Which kinds of vegetable grows best (good) in your hometown?在你们家乡哪些种类的蔬菜长得最好？