I'd say go for cornfields as they are already fertilized and properly irrigated. This is what I use. Disadvantage with this in my area is that plants cannot be put into fields until early July (otherwise corn is too small), and need to be harvested by around mid'September before corn is chopped. Despite the short season plants grow tall and yield well due to great soil/moisture conditions. From a little clone put in July 10 I can yield up to 250 g per plant, no joke.
