White marigolds don't come burdened with a bunch of limiting factors, that I know of. Is this particular pot of marigolds being treated as one would treat other sun loving annuals? Good potting medium, plenty of sunlight, conservative but regular doses of fertilizer, etc., etc. These are tall plants, aren't they? Have they reached their adult size, yet?

They have all of those factors. There are a lot of them in one container. I am wondering if it is too much nitrogen. Would that do it? Can I counteract that?
Thanks for answering. Everybody busy, I guess. -Barb