The best site I've seen has no dirt it's basically all rock with some plants holdin it together here and there. Is it worth it to put about 400-600L of earth enclosed in a bed upthere or would it dry out really quickly on the sunny rocks like small pots did last year? The area in question is really rainy and plants in the ground rarely need watering plus the morning mist should provide a fair amount of water. Wonding if its worth the hassle, site gets good sun and others dont compare.