Answer: I would suspect that the plants were overwatered if mold formed on the soil; this could also have caused the seeds to rot. However, it is difficult to tell exactly what happened. I'm sorry I can't be more helpful. Since this is a science fair project you might want to discuss it with your teacher or look at the following site called Cyberfair http://www.isd77.k12.mn.us/resources/cf/ which has lots of useful information about experiments in it. I hope this helps.
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