After my little time-trial with the k-cups yesterday, and then looking around here today at my hord of plastic recycling(and other junk), i thought i should return to looking at prices on tall tree pots(i sort of mentioned this yesterday). here is what found top of the page on google:

https://www.amazon.com/Seedling-Treepots-Container-Starting-Drainage/dp/B0BPM5HXJ1/ref=asc_df_B0BPM5HXJ1
50x 10" tall
$18(free ship options)
 ~$0.36 each

https://www.amazon.com/Hzloyat-Plastic-Nursery-Seedling-Container/dp/B0CSWL8WKJ/ref=asc_df_B0CSWL8WKJ
50x 12" tall
$21(free ship options)
 ~$0.42 each

https://www.247garden.com/10-pack-1-2-gallon-skinny-tall-black-fabric-pots-deep-aeration-plant-grow-bags-4d-x-10h.html
10x 10"H
$10 (+shipping?)

https://www.247garden.com/247garden-2-gallon-skinny-tall-black-fabric-pot-6d-x-16h.html
1x 16"H
$0.68 (+shipping?)

https://www.greenhousemegastore.com/products/treepots
$245(shipping?) for 300x 4x9"   ~$0.81 per
$258(shipping?) for 210x 4x14"  ~$1.22 per
$253(shipping?) for  96x 6x16"  ~$2.63 per

https://www.groworganic.com/products/tree-growing-containers-treepots-tall
$2.40 for each 4x14"(shipping?)

So, basically we are looking at roughly 50cents up to acouple dollars each for the size i want. I'm disreagarding lowes and homedepot because they seem to focus more on expensive resin pots, and i don't think they sell cheep pots. disposible picnicware from walmart is also potentially cost-competative, but is generally smaller than what i want. i guess the only question now is how fast i can turn plastic shopping bags + food wrappers into potting tubes. the procedure is a bit more involved than simply cutting holes in yogurt cups. At this point i have a little stash of recycled sheet material i made from the bags using teflon oven liners and a skiwax iron, and i think i have an idea using the same tools for turning the a sheet into a tube. I'll have to time myself next time i give it a go. We will see if i am anywhere near a cost effective rate at producing the tubes. alternatively, i am also thinking about making plastic tiles; i guess the idea there would be to tile my crawlspace? expect a blog-post some time on https://trygve.neocities.org/.