material to create a fabric-based olla for irrigation

Ok, I’ve come up empty from asking this question of the few engineers I know, so I realized I should resurrect my Straightdope account to tap into some creative thinkers.

Olla irrigation pots are terracotta pots that are not glazed and, thus, porous. They are buried in the ground up to a narrow neck that allows them to be filled with water. Over the course of a few days the water in the pot seeps into the ground. The alleged benefits are that this prevents water lost to evaporation, is less likely to water seeds of weeds that are on the surface of the soil, reduces labor from watering as often, etc.

However, terracotta is fragile, bulky, not frost resistant, etc. Ollas that I’ve seen cannot provide water to plants more than a couple of feet away from the pot. (Some people make more affordable ones about of gluing two flower pots together and closing off one drainage hole and using the other drainage hole as the input point. Still, the same problems apply.)

So, here’s the question: If the water and labor saving advantages are real, as well as the benefits of providing water below the surface for roots, is there a fabric or similar materials that could survive several years in the ground, is affordable, can be easily folded and unfolded onto a frame, and would allow water to slowly enter the ground?

I’m thinking, fellow do-gooders, of a device that low-income farmers on small plots could use to save water and labor after installation to irrigate larger spaces than a clay pot can. Perhaps it would be a long tube that you put a foot or so deep in a trench between your crops. Then you fill it with water at one end and stop when water comes out the other…(also helps with knowing if the tube has silted up).

Make sense? Any ideas of an affordable fabric or material or whatever that would fit the bill? If you say reverse osmosis material, can you explain how complicated that is, how expensive, what additional tech in need to make it work, and if it fits the other requirements?

Thank you.

I don’t know about fabric, but there is a porous rubber material that might be a starting point.

Fabric would generally work too quickly. There are situations in which you can use a small deposit of waxed denim or double nylon cloth (a cone of woven nylon inside another one) but it’s for small amounts at very short distances, for very short times (a few days, couple weeks tops and this requires very humid air); the drier the local air, the less the water will last.

But your deposits could maybe be combined with riego a la gota. Riego a la gota (drop by drop irrigation) involves long tubes sitting on the floor, distributing relatively small amounts of water directly to the plants. The tubes are of materials similar to those I mentioned for the small deposits: something like waxed cloth is nonporous where the wax is intact, porous where it has broken. Instead of connecting the entry point of the tubes to the irrigation ditch and switching them off as needed, it might be possible to have them connected to a deposit which gets refilled, with a ball valve at the connection point.

Aren’t ollas used mostly in desert areas?

Back when I had a backyard garden, I used plastic jugs with holes poked in them, some partially buried, others not.

You can use ollas in any situation or even tiny ones in large planters. Plastic jugs degrade fast in the sun and holes in them don’t release water slowly.

The idea is to bury the item so water is seeping into the soil several inches or more below the surface. Would wax denim last long in the ground? Thanks for the idea.

Perforated oilcloth.

La gota is specifically on the surface, partly because otherwise maintenance would be hell. Underground* gota* systems are more expensive (you need more-specific tubing) and a pain to maintain (you can’t review the state of the tubes without either using expensive sensors or unearthing them); it’s the kind of thing that’s much more likely to be used by some professor who, in the words of my farmer-with-a-phD-friend “had never cared for a geranium before deciding to get a degree in Agricultural Engineering”, than by a real farmer. But then, irrigation usually takes place on the surface.

I think this is your easiest route. Soaker hoses work well and the flow can be controlled. I thought they were fabric but it seems they are rubber today. So they should not deteriorate too quickly.


Soaker hoses are great in theory, but the last time I maintained a garden I found that my water was too hard–the hoses very quickly became crusted in minerals and water stopped seeping through. Mineral deposits were a problem on my drip irrigation system too, but less so. Something to consider.

As for the olla solution, this strikes me as something likely to break about 5 minutes after you spent hours digging the hole and then carefully filling in around it. Then you’ve got a sinkhole filled with pottery shards.

ETA: Sorry, I didn’t really address your fabric question. I can only say that in my time as a low-water gardener, I never came across anything like what you describe.

I’ve never done it but I’ve heard the insides of diapers can do a something similar.

Looks like they are called “super absorbent polymers” and you can buy them specifically for gardening.