I had discovered a marigold sproutling beneath a large potter on our pool deck.. it had germinated in the landscaping stones where there was no dirt, just space between rock. I was weeding the area when I plucked the little plant, noticed its similarity to the marigold in the large container just in front of me and said, "This must be a marigold.."..
I moved the little sprout to a very small container where we watched a venus fly trap wither and die... and sure enough now there are countless marigold blooming flowers from this tiny container sprout.. which I thought was a weed.