As it is now, it's great that we have to irrigate the crops. But the problem in my opinion: No way to construct an automatic irrigation system and that land based crops will pop off the ground if they have 1 block of water over them. The farm row does get irrigated with 1 block of water, but it will most likely pop the seed off the ground. The whole submersed farm rows do work with underwater crops, as they now require to be submersed and they need no separate irrigation. Although it didn't work like this before, I used to construct farm rows under 1 block of water, as if it would usually be with rice crops as I've seen in real life. Perhaps make land based crops resist atleast 1 block submersion? Well, hopefully new functions come out someday, like "plumbing" to construct water transfer system for elaborate systems like automatic irrigation, hand build water fountains, underwater pressure chambers and etc.