I've come to realize no matter how well something can grow in soil, it can grow much better in a hydroponic solution.
If that's true, why do people still garden in soil? Probably for the same reason I still have raised garden beds. Soil is still the only acceptable medium for growing fruits and vegetables, at this time. Industry is geared up for soil gardening with cultivators, hoes, hoses, fertilizers, pesticides, and bagged soil of every kind, creating sub-industries that rely on the warmer months to keep their businesses going. The cost to convert hundreds of acres of farmland to greenhouses is out of the reach for the small family farms and the giant corporate farms are run by ADM, Monsanto, and a few other corporations, heavily invested in GMOs and chemical farming, who aren't about to cut their own economic throats.
Not so in other parts of the world. Ontario, Canada has massive greenhouses a mile long that can grow anything, year round, with climate controlled efficiency. Sure, it costs millions to build one of these greenhouses but they pay for themselves in a few years. After that, it's all net. And they do it hydroponically.
Compare that system to earth farming that requires a million dollars worth of farming equipment before you break soil. Not to mention dealing with Monsanto as a business partner, intensive labor, irrigation, storage, weather concerns, equipment malfunctions, and the risk that your whole crop could go bust. Any soil agribusiness could lose it all without a hedge fund to counter potential losses, further reducing profits. Not to mention, all that GMO food laced with
glyphosate costs more, has little to no food value, and will keep you sick for the rest of your life.
In my limited experiments with hydroponics I learned a few things that could radically increase my bottom line, if I was in the food producing business.
This hydroponic system has been running a little more than a month and I began harvesting greens within a couple weeks of planting. No weeds, insects, or rabbits. It's all at waist level so there's no back breaking work. Startup cost is extremely cheap and easy. Daily maintenance takes minutes and only requires mixing a solution once a week as the major duty. It's portable and can be run indoors. With lights and a timer you can produce just about anything, year round. Exposure to soil bound bacteria and parasites is a non-issue.
But what about larger plants like tomatoes and asparagus?

I'm working on it.
The five gallon bucket to the left has a nutrient solution with an air stone to oxygenate the water that feeds the tomato plant in a perforated cup filled with an inert growing medium.
Theoretically, adding a light and keeping it indoors during the colder months, this system could produce indefinitely, year after year.
And it all comes back to growing indoors for a reason. In a SHTF scenario, there's a very real possibility that air and soil contamination could threaten the food supply. Rather than prepping by stocking up on canned food that will be gone in a few months, why not grow your own, indefinitely? A few solar collectors and a little technology could easily turn any system totally off-grid. An unheated basement with a little floor space is all you'll need for perpetual, food sustainability and independence.
Just think what you could do with cannabis.