BTW, I'm not talking about "Newspaper pots", I'm thinking of something bigger for planting up tomato and peppers etc.

Best Wishes
Amino-X

Is this what they mean by "paper machet"?

Here is a link that might be useful: previous discussion here on GW labs

Do you mean you want to make discs that would expand when watered for use as pots?

If so, that might just work to an extent.
Paper pulp is best fresh. If you dry it out and then re-wet it you have to work it a lot in order to get the orig. pliable dough texture back. I think that feature, which is annoying when working on art projects and making a lot of pulp in advance, would be useful for pot discs. A disc that wasn't over-watered would hold up pretty well for a while probably.

I'm not sure if it would expand with the same quickness and loft that peat moss discs do though. Also you will likely encounter some mold (ever try starting seeds in a glass between the side and some paper towel so you can watch the seeds sprout? that yellowing you get along the top of the paper after a while you will see on the paper pulp pot) within a couple of weeks (sooner in a covered flat, which will also likely spore and smell).

If what you wanted to do was make pots out of paper mache using paper pulp, that will work just as well as any other pot. You'd need a sealant to keep the pot from dissolving though. I'm planning to do this myself, but with papercrete (paper pulp, dirt, sand, small stones, and perhaps cement) so I get a carved out stone look to the pots.

Now I'm curious as to just how well newspaper would work as expandable pot discs. I think I'll make some and see what happens.

Amino X:
I know what you mean. This idea floated through my head a couple of months or more, ago.
This would be like making pots out of the same papery mush that egg cartons are made of . (Not like the Jiffy pellets that are all peat moss and expand when watered.)

I think it would work if we had molds made up. You'd need an inside "cup" and an outside "cup" about .25 Inches diameter difference. The void between the two cups (when nested one into the other) would be filled by the slurry of paper. Then you would have to squeeze out as much water as possible, unmold and see that the darn thing would not collapse in the drying process. Hm, and you might need a binding agent in the paper slurry too...or it may come apart as you water the seedlings. (That would be a bummer.)
This requires a well thought out plan, but I can't see why this wouldn't be a good do-it-yourself-project.

Best of luck!
Maryanne in Massachusetts (who used to be a mechanical designer, believe it or not!)

If you are looking for a substitute for the hollow pots: Someone posted a way to convert toilet paper rolls into pots. Just fold them so they are four sided, cut part way up the folds, and fold the flaps in. Have not tried this yet.

If you are looking for a substitute for peat disks: I think the reason for the expansion is simply to save space in shipping and because it looks cool as it happens. Why compress the substitute if you don't have to? This may simplify the process, but will slow drying.

Flour acts as the mastic in paper mache. I would assume that flour with sugar would provide good nutrition in the substitute pot.

I found that mouthwash acts as an antifungal in water based paint (Got this out of an old book and it really does work.) Maybe mouthwash incorporated into the pot with the rest would set up a pot that would support growth well and resist damping off.

The "paper pot" idea can be adapted to larger size pots by adding more layers of newspaper. I find an approriate size container to wrap the newspaper around, add as many layers as seems needed for strength, crunch in the bottem and fill with potting mix. The water seems to bind the layers together. I suppose you could paint the layers with the paper mache paste as you go, but I haven't found it necessary. This is for a pot I can transplant directly into the ground later, without removing the covering. It wouldn't work for something that was going to moved very much.

Marty, how long will the large paper pots last? How many thicknesses of paper do you use? Your idea is quite intriguing. Thanks

Good that I came across this forum as I have to make 44 5" newspaper pots. I found that a Quaker oats container works fine to roll the paper. I put a fold on the top lip before I roll, then when in a circle tuck one side under the other. I put a cut on the bottom, fold one side down then the other with tabs left which I staple to the sides then put a couple more staples to keep the top together. Seems 5 staples will do it for a 5" newspaper pot. I'm planning to put the 3" peat pots at the bottom for water absorption, then put a hole or two for drainage as the newspaper won't suck as much water as the peat pot. I think they'll also look better when given out as gifts, which about 10 of them will be. Should work okay.

I am no good at bending or kneeling over ground-level garden rows. Besides using raised beds, I am experimenting with making half-tubes (U-shaped cross-section) out of paper slurry. I want to plant an entire row, or half a row, in early spring, indoors, and then in warmer weather, move the entire row in its coarse paper half-tube into the garden or raised bed. No bending over, planting seed by seed by seed.

I'm thinking of useing egg carton bits to increase capillary action in my hydroponics growing media. I discovered a way to sub the perlite and vulmiculite mix,drywall compound,mixed with very little water,and as it sets I crumble it very finely. Bb sized bits.after a 24 hour cure it works just fine.I subed sawdust for coffee grounds (used),and I used large bits if natral mulch from my garden, no dirt of soil,I screened that out.it drains perfect,but I fear its not wicking well.I'm useing self watering planters,large cotton cord as wick.I set the wick about half way,to encourage root growth.I think the top is to dry still.if I add just a small bit of crushed egg carton,will this help the capillary action with out effecting my drainage and breathibility?I'm thinking bb sized bits.

Seeing no response,I tryed it any way.so far its working as I hoped.I'll moniter to see how well it wicks but after 12+ hours the egg cartons bits are still as wet as they was when I rehydrated them.I also noticed the slightest drop in my water resivoir. Fingers crossed, maby I'll be droping a seed in very soon.ill post pics of my set up only if people are interested. As an additional hydroponics experiment I plan on useing live sphagnum moss as a medium. In theory it would be the best hydroponic media. Carnivourus plants do perfectly in it,without the hydroponic system fueling it.ph levels and tds is my only wild cards...,moss of any type takes in nutes and moisture from the air I believe, and I doubt the moss would cash my nutes very fast any way.it will be fun to try,I'm trying to get some sphag moss now to grow and propagate.