I'm curious - what do you use for growing seedlings? I'm trying to get away from plastic, and I need some of my pots to be larger than normal as I am planting tree saplings. I'd like to reuse or recycle materials that might otherwise go in the trash.
I know you said you were trying to stay away from plastic, but you also said you would like to reuse/recycle. I use 1/2 gallon milk cartons to winter sow the honeylocusttrees that Dan Boone sent me. They will be planted out this spring and they aren't even up yet.
Since you're using them for saplings and not seedlings, I would suggest gallon milk jugs with the top cut off.
I have a battery operated soldering iron to make drainage holes in plastic. For paper cartons, I use an ice pick.
How long do you need these pots to last for? There are a lot of natural materials that can be used to make grow bags, even repurposing old burlap sacks. They'll eventually decompose, so you can't use them indefinitely.
For small seedlings I like pressed paper pots, but I still find it beneficial to tear off most of the temporary pot before planting. You could probably fashion a similar pot from cardboard. If you have access to any wax you could coat your materials and that might slightly extend the lifespan.
I use the inners out of toilet rolls for slightly bigger things like beans, not sure if they would be big enough for your tree seedlings though....
Stand up a bunch of toilet roll inners in a seed tray, fill them with compost, plant seed, top up, water. You can plant thw whole thing, but as someone else mentioned, it is best to take the top of the 'pot' off before planting - it can act as a wick to draw moisture up and out of the soil
Thanks all. Some great ideas here. I especially like reusing plastic as much as I can. If it's already there, it should pay it's keep. Or some of it. Also, using cardboard tubes is cool. Given that I'm looking at trees, I may use paper towel rolls rather than toilet paper, and possibly increase the size by cutting 2 in half long ways and gluing them together.