First,
from CA!
To your question: From my experience (was an organic farm-hand for about 3 years in college & studied horticulture for a time, and worked in plant industry in Holland) snails are a problem for any leafy green plant.
If I recall correctly, snails, slugs and aphids are going to be your biggest problem pests.
There are some low tech solutions to snails of you don't like using snail bait. My favorite is copper. Copper is more expensive than it was 20 years ago when I was using it though. We'd wrap the legs of the greenhouse benches with copper wire - which contains a natural electrical current. This is like the electric chair to your mucus-sliming friends. They simply will not cross it, which keeps everything above on the benches snail/slug free. Aphids are another story. The biggest issues I had with Aphids were ant farmers.
See ants are extremely clever in one regard: they will "farm" aphids. Ants will actually pick up an aphid, bring it to your plant, leave it there to feed, wait for it to poop its sugary resin, and collect the resin. It's fascinating as a marvel of nature and frustrating as a grower of anything.
But back to your question, yes - Snails are the enemy. Copper is your friend. Works great. I did a quick google to see if science backed up my old wives tale (even though anecdotally I had GREAT success with copper wire) and found this:
http://www.usc.edu/CSSF/History/2004/Projects/J1920.pdf