Oh man! It seems liked it would have worked... I have bad luck with carrots to begin with.
Find a 10 gallon aquarium from someone who doesn't want one anymore fill with dirt cover outside with black paper, make it easy to remove to peak at. Plant seeds close to sides so you can see things grow! A few worms make it interesting.
I wonder if putting something in there as sort of a "wall" to force it closer to the outer wall would help? I also wonder if perhaps anonymous' idea is a valid one. Perhaps they need the dark?