Experiment 1: How durable are home-made cardboard seedpots?

Because I am always interested in reusing items and at the same time finding fun things to do with gardening, I decided to look into making my own cardboard seedpots. Many of the instructions I have found online have mentioned using newspaper (which I can't see lasting too long with slow growing indoor starters) so I opted to find some info using paper towel and toilet paper rolls.  I found a good set of instructions here:

http://www.ehow.com/how_4849130_seed-starter-pots-cardboard-tubes.html

So I started a few and decided that I wanted to test how durable these actually were when exposed to large amounts of water and continual (hopefully) plant growth.

For added fun, I doubled up on some of the cardboard to see if that increases durability or hampers plant growth.  Starting with 3 singles and 3 doubles,  I then added some Miracle-gro potting mix, a few Marigold seeds, and 3/4 cup water.

Doubled pots -top row