I’ve heard about that, good stuff for shallow early roots. Pierce holes in the bottom and they go right into the ground.
Great ideas. Thanks.
That’s about what I thought. I guess the next thing to do would be to try knitting cat hair potholders for the fires started with the egg cartons. 
My grandma used to make wastebaskets out of them: Take three (I think) egg cartons, stand them on end vertically, attach the front lid edge of one carton to the front bottom edge of the next, and bend them into a circle so that the insides of the cartons are on the outside of the “wastebasket.” I think she may have glued a circle of cardboard on the bottom. Glue pictures from old saved greeting cards in the flat lid sections. Add paint/glitter as desired.
Grandma was a real recycler. 
It just starts that way, next thing you know, you’re dead and it takes your grandkids FOUR 20 yard dumpsters to haul all the useless crap out.
Since eBay’s appeared, I sell mine. A box of 100 goes for about 10 bucks, plus shipping.