The best garden experiment I ever conducted was last year - determinate tomatoes in grow bags, sitting in a kid’s wading pool. I stuck cheap wire supports in the bags so the plants stayed upright. Covered the potting soil in the bags with a nice layer of compost. The tomatoes grew beautifully and I harvested more tomatoes from the bags than the other six plants that were in raised beds.
This is the video that gave me the idea:
https://www.youtube.com/watch?v=Wf5fB3fnTuE
I did not use the gutter system, but just put the bags in a plastic wading pool. Watering was super-simple, just filled the wading pool with the hose. Plants sucked up the water without a problem. I purchased the shopping bags from Amazon in a lot of 15 for $10.
I soaked some unused adult diapers in miracle grow water - boy do they swell up- and they’ll hold about a gallon. Then I tear open the diaper and remove that gel that formed and mix that in with the potting soil in the biggest pot, foam cooler or tub I can find. I planted tomato vines in there, burying 2/3 of them with just the tops sticking out. The gel reduces drought stress between waterings. So far they look awesome and husky. Did eggplant that way too.
This is Florida, I use fresh soil mixed with rabbit and chicken manure and lots of old eggshells rather than waste time with our sand. Fresh soil with manure - to avoid the nematodes that plague us. Haven’t tried baking old soil, usually I just use the old soil from last year’s tomatoes to grow Swiss chard.
My parrots’ used wood pellet cage bedding goes on top of the soil like mulch to hold in moisture and provide a little fertilizer.
That is so cool!!! Yeah, the guy in the vid has to sort of balance his plants on a gutter. Your idea is even better. I’m taking it the pool is dry, then when you water, you hose it into the pool and in an hour or 2 or three it’s dry again? So the roots aren’t soaking in water?
I love this idea!! Fifty cent grocery bags! So cool.