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Solar Capillary Irrigation Answered

I was thinking: If you used a post hole digger and made 2' or 3' holes throughout the garden, then dropped an old pant leg or other scrap fabric down the hole, filled it up with soil while leaving some fabric exposed above the soil, covered the fabric with an inverted clear plastic or glass bowl, would this draw enough moisture through the fabric to irrigate the plants near the bowl? I'm thinking the sun would heat things up for condensation on the glass which would drip down the sides to the soil while capillary action would draw deep soil moisture through the fabric to the surface where garden plant root zones are. Anybody try this before?


This might help even out your water supply but I agree with the other posters that you are not adding water to the system, and that the soil already has a capillary action. I am wondering if you live in an area where there is sporadic rainfall, you might be able to create mini cisterns by putting a large soda bottle with the neck cut off (or similar vessel), and stuff the bottle with the fabric before you bury it. That might make a mini-reservoir of water that would then wick up when the soil became dry... especially if you have clay soil that water runs off of when it rains.

The root zone of many garden plants is pretty shallow, I guess this is an attempt to make artificial roots with transpiration powered by the sun, similar to plant processes.

. If it works, the bowl probably won't be necessary - capillary action will provide the power. Just bury your wick and plant the flora on top of it. . . If I understood the Wikipedia page (link below, so you can double-check), the water will wick from the damp end to the dry end, so it should be somewhat self-limiting (ie, once the roots get as damp as the far end of the wick, wicking will stop or at least slow down).

I don't think you'd need the bowl, presuming the fabric drew up water with capillary action then contact with soil particles should draw the water out at the surface.

Where is the condensation (that forms on the bowl) coming from? Answer: the soil. I.e. you're not adding any water to the system. L

. I think he's talking about wicking subsurface water up to the bowl where it will evaporate and then condense around the edges for distribution. . My hypothesis is the same as your's - "not adding any water to the system," but I'm not sure. It might just work.

Wicking will occur in the opposite direction also. I suppose it depends what the ground is like. But plant roots go downwards to get the subsurface water anyway. L

. Any idea how far water can be lifted by wicking? A few inches? A few feet? Or does each small group of fibers form a new capillary, so that the the lift is unlimited?

. Interesting idea. . I can't put my finger on it, but something doesn't sound right to me. I'm _guessing_ that the capillary action of cloth in dirt isn't going to move much water. Doesn't dirt exhibit "capillary action," ie, it will draw water up, similar to cloth? If it works, you may just end up drawing water away from the plants, then re-distributing it to the plants - no net gain. . Run a few experiments and let us know what happens. Hopefully I'm wrong. I would think that the coarser the fibers/weave (eg, burlap, instead of denim), the better, but that's just a guess.