Sight unseen, my first guess would be algae. Algae are green, because they contain chlorophyll. We see them thrive in very moist environments...that's a requirement. So, your potting medium might be too wet, or too dense, or too slow to drain. Poor air circulation can also contribute to algae growth.

Oh swell. I've already made some adjustments because I believe my soil isn't draining well. I'm afraid to repot lest the young plants get upset. The plants are actually starting to look better. I believe they had fertilizer burn so I flushed the pots once. They are buried halfway in my garden. Perhaps I shoukd drill more holes into the buried portions to allow more drainage into the native soil.

I love gardening but I feel I'm failing. And if I spend any more $ my hubby is not going to be happy :'-(

I haven't ever heard of algae film on potting mix actually harming a plant, so if you can take care of the drainage they'll be fine. Look at the bright side: at least you don't have to subsist on whatever you can grow! :-)