I hope this has resolved for you by now. In my experience most of the time the plants just "grow out" of it as they get their roots established and start drawing up nutrients. Also, this time of year, with pretty low temps in the night, can cause that yellowing too. Remember to snip off the yellow leaves once you have green healthy leaves in place, because yellow leaves are a signal to bugs to come and eat. Now that we're into June, I bet we really see our gardens boom!

I resolved the issue by applying fish emulsion on a weekly basis. My main culprit was using a composted manure mix that wasn't quite finished and, according to my research, will result in a nitrogen lockup in the soil. I have found a better manure mix so that seems to be doing the trick.