Did I ever show which paper pot method I settled on? I’ve tried various methods for making paperpots, including glueing, stapling, taping, as well as no-fastener origami. My conclusion has been that methods requiring cutting papers to specific size and/or dimensions as well as those requiring fastening device are too time-consuming. My time is limited.
Newspaper, etc. thinner papers no matter how many layers are too flimsy.
I had tried toilet paper (TP) and paper towel (PT) core tubes in the past and failed. Several issues — open bottoms tubes resulted in lost potting mix and unacceptable subsidence. While kitchen paper towel tubes feel “cleaner,” they need to be cut down to size which disqualified them in the end in addition to the above issues. Cutting TP tubes in half was rejected.
They also tend to end-up with weird mushrooms growing out of them, or mildew, and other fungal growths. There was also the issue of too much moisture retention similar to peat pots, etc. Also, often seedlings ran into N deficiency/deprivation when the roots came in contact with the yet-unbroken down tube wall.
...HOWEVER... I kept going back to the TP tubes because the diameter and height of the tubes/depth for the roots were ideal for certain kinds of seedlings, especially ones that don’t like to be disturbed.
Well, I discovered that the fungi and moisture problems is partly a question of using a container for the tubes that drain excess water from the bottom and is more breathable than plastic. Using cinnamon and chamomile tea as fungus gnat preventive also helps to reduce fungal growths. Also, choosing seedlings that grow relatively fast and do not need to be kept in the tubes for too long, and are resistant to fungal contamination from these kinds of fungi. I also realized the N-deficiency issues could be overcome without burning the roots by introducing compost worms to the soil after the seedlings reach a certain size. They also help to break down the tubes faster and create weak spots for the roots to grow through, but I decided to help the roots even more.
I fiddled with the structure and assembly some more — this is my current design:
1) use a pill bottle as depth and base folding form.
2) cut 8 vertical slits in the sides to help the roots escape
3) 9 tubes fit with a little deforming in a straight sided ice cream tub.
4) after the tubes are all in, cut upside-down V between the tubes along the base of the tub just above the bottom for drainage.
5) put a leaf or a pice of paper in the bottom of the tubes before filling to temporarily keep mix from falling out, and use a cut-off plastic bottle funnel to direct the potting mix.
Ice cream tub fits well in a Chinese take out tray as drip tray. I prefer white ones for light reflection.