Yes. It is a mini greenhouse. It retains heat and will create condensation inside the greenhouse. This provides moisture for the seeds. If it creates too much condensation, just lift the plastic top a little to vent for a day, then replace the lid.
I don't think there's a too old. I reuses mine if I have to. If the seeds I put on the pellet don't germinate. I save the pellet to use again some other time.
Not to my knowledge
I don't think so. I can't find 'organic' label anywhere on the package.
I would not add fertilizer until plant is established. Mine grew well without any fertilizer added when planted in ground. Pellet supplied plenty of nutrients.
yes.... Not sure about the smarter part, depends on your experience and expectations.
per http://www.jiffypot.com/en.html "Available in two sizes: 36 mm and 50 mm in XXL pellets"
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