Here's a good thread, but it's more about "finding" than "making":
The thread "Ideas for cheap plant pots" in
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Personally, I watch like a hawk at all times for discarded plastic containers of any size with straight walls. I grab them, clean them and save them in big garbage bags on the back porch.
Thus do I strike a blow for re-purposing!
- Two liter soda bottles are a handy size: 4 inch diameter.
- I have many sturdy Sobe bottles with annoying ridges: 2.7" diameter.
- plastic Solo cups and Dixie cups can be cheap and come in many small sizes
- Dollar Store and Goodwill have plastic tubs & pails
- 4 & 5 gallon buckets are where you find them
But only use straight-sided containers. You can't ever get the plant out of a "wasp-waist-ed" bottle. But I guess you could cut the pot off when ready to re-pot.
I used to live next to a delicatessen that threw away a few 4-gallon plastic pails per week. Those were too tall for most things, but here's one nice thing about "free": you're not being wasteful if you cut off and throw away half of the pail or bottle.
- fast food places (e.g. pickle buckets)
- delis (dumpster-diving brings many useful things to light!)
- bakeries
- deli & bakery departments in supermarkets
- paint and Spackle buckets from contractors (clean them WELL)
- Home Depot SELLS five-gallon buckets
When I need more of a certain size pot, I drill or melt many holes or slits, always making sure that holes on the bottom DO have open access to air so oxygen can diffuse into the roots. Then I cut or melt some side slits for ventilation anyway. Roots need air even more than they need water!
I'm thinking about how to make easy, free, micro-Earth-Boxes out of 2 liter bottles. The cut-off top, drilled, plus some window screening, could be the "colander". The "reservoir" would be very small, just the bottom 1/2" to 3/4" of the 2 liter bottle.