I posted a few weeks ago about my failing basil plants. As a last resort, I moved them from the pot they were in, to my Square Foot Garden, which has very fertile soil. They did not seem to be improving. I went out of town for the weekend, and today they look great! I don't know what happened, but they suddenly caught up with themselves and are looking good. The leaves are all dark green again and the uppermost leaves have even grown larger. I still don't know what the precise problem was, but it was something to do with the soil in that planter, or with being in a planter, period. Moving the basil seems to have solved the problem, even though it took a few weeks. Thanks for all the suggestions!