Nettles, Nasturtiums and Snails.

Last night I took my neighbors a tomato, and they were so pleased they invited me out back to see their urban garden. They had made excellent use of every available spot. Their tomatoes are just starting to fruit so they were happy to get a ripe one from me. Their garden was so tidy and lovely, not at all like my jungle, even though our yard layouts are identical. When I mentioned my problems with snails, they told me in a rather confusing discussion in broken English and Romanian that they use nettle spray to repel the snails.  They get the nettles from a park, boil it in water to make a soup, then spray it on the plants.
While researching that on the Internet, I came across this site on companion planting. While it didn't say much on the nettle thing, the bit about nasturtiums has me inspired to plant nasturtiums all around my tomatoes. I had nasturtiums all around them before from volunteer seedlings, but they got dug up with the weeds and grass we had to discard to plant the new tomato sets. I have a few left in the other flower bed, and the hummingbirds have been feeding from them. I want to make some nasturtium salad too. I keep reading that you can eat them but I never remember to try it.