Pod Insights Stuff You Missed in History Class The Rise of Modern Hydroponics About this episode The practice of growing plants in water rather than soil isn't new, though early examples are difficult to substantiate. In the 1930s, hydroponic plant culture made headlines, but the field also had conflict among researchers.
Transcript Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.
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2:15 Holly Frey? Welcome to Stuff You Missed in History Class, a production of iHeart Radio.
2:26 Holly Frey? Hello and welcome to the podcast. I'm Holly Frey.
2:28 Tracy V. Wilson? And I'm Tracy V. Wilson.
2:31 Holly Frey? Uh, I bought myself a big old hydroponic garden system for Christmas.
2:35 Tracy V. Wilson? You've been so excited about it.
2:36 Holly Frey? I'm obsessed with it. I'm obs- I can't even describe all of the levels of obsessed I am with it. And we could talk about my various adventures in gardening on Friday, but um, I am obsessed with this. Which of course, anytime I become obsessed with something, I wanna watch a million videos and look at a bunch of articles. And it got me thinking about like, how did we get to a point where a company will be like, oh yes, we'll sell you a thing. You don't really have to do much, but suddenly you'll have lettuce in your house that is grown right there.
3:07 Holly Frey? And that got me down the rabbit hole of hydroponics history. And also frankly, the garden is one of the things that is keeping me from losing my mind in our complicated days.
3:20 Tracy V. Wilson? Yeah, yeah.
3:23 Holly Frey? So perhaps for other people that are having stressy times and complicated days, thinking about plants growing and how sort of um, mentally and emotionally nour- nourishing that can be will help you as well as me. So we're gonna talk about the history of hydroponics today.
3:44 Tracy V. Wilson? Using water rather than soil to grow plants is not in the least bit new. Although the earliest uses of this technique are not well documented. Some examples, like the Hanging Gardens of Babylon, have to be discussed as possible examples. We don't even know for sure if the gardens, which are considered one of the seven wonders of the ancient world, were real. Accounts written about them were penned centuries after they were said to have existed. And there is no conclusive archaeological evidence to point to. If they did exist, their likely location was right in the middle of modern day Iraq
4:29 Tracy V. Wilson? and very possibly not Babylon, but Nineveh.
4:34 Tracy V. Wilson? If the gardens did exist, it's possible that their terraces full of greenery would have been supported by an irrigation system with water brought in likely from the Euphrates River. All of this, very cool, but still, this garden and the technique dated to the 6th century BCE are all theoretical. Additionally, while some historians interpret the existing writing about the Hanging Gardens of Babylon as indicating a hydroponic system of some sort, others think that the terraces described involve some sort of soil or sand substrate as a medium that the plants are growing in with the irrigation being used to water that substrate.
5:17 Tracy V. Wilson? Basically, there's not agreement on this potential example.
5:22 Holly Frey? Not at all. Another instance of an ancient plant cultivation that isn't hydroponic but does represent an important step in the idea of growing plants in a controlled environment is the story of cucumbers, maybe, we'll get to that in a moment, grown year-round for the Roman Emperor Tiberius. This is a practice which was recorded by Pliny the Elder in 77 BCE. He wrote, quote, "Cucumus was a delicacy for which the Emperor Tiberius had a remarkable partiality. In fact, there was never a day on which he was not supplied with it, as his kitchen gardeners had cucumus beds mounted on wheels, which they moved out into the sun and then
6:04 Holly Frey? on wintry days withdrew under the cover of frames glazed with transparent stone." So while he is describing plants grown in soil, they're also being raised on a wheeled apparatus which can be moved indoors or out and which has a cover. So this is clearly an early greenhouse. And incidentally, while Pliny's reference to cucumus is often interpreted as cucumber, a paper published in the Annals of Botany in 2007 and written by Jules Janik, Harry S. Paris, and David C. Parrish notes that, quote, "The cucumus of Colomella and Pliny was not cucumber, as commonly translated, but cucumus mellow subspecies mellow flexiusus group." That's snake melon or vegetable melon.
6:50 Tracy V. Wilson? The next historical precursor to modern hydroponics is the 11th century chinampas of the Aztec culture. This is a case where the nutrients that fed the plants were part of the naturally existing ecosystem, but there was a lot of human effort in establishing the gardens known as chinampas. Lake Socimilco, which is south of Mexico City, was and still is the site of a unique and extensive garden system that's based on human-made islands. These islands are made using mud, dirt, and grasses and other plant material, and then they are staked into the bed of the lake.
7:31 Tracy V. Wilson? These islands could be as large as 10 by 200 meters, or 35 by 650 feet. And then into those floating islands go seeds. The water and the nutrients of the lake, including fish waste and decomposing plants, offer a rich mix of nutrients distributed by the water's natural movement.
7:53 Holly Frey? Yeah, there is also a significant amount of argument about these and whether or not you can really call them islands, because some are connected to the land, etc., but there's still a pretty cool effort in hydroponic gardening. In 1627, Sir Francis Bacon's book entitled Silva Silvarum was published. This was a posthumous publication, because Bacon had died in 1626. But it is often called the first book of water culture, because it features the passage, quote, "The water also doth send forth plants that have no roots fixed in the bottom, but they are less perfect plants, being almost but leaves, and those small ones.
8:35 Holly Frey? Such as that we call duckweed, which hath a leaf no bigger than a thyme leaf, but of a fresher green, and puteth forth a little string into the water far from the bottom. As for the water lily, it hath a root in the ground, and so have a number of other herbs that grow in ponds." So, he recognized that some plants seemed to not need soil and could actually float on top of water. But this is an interesting read if you ever go digging through it, because he also thought that plants would change species if you neglected them, so he had some things a little bit confused about the natural world.
9:11 Tracy V. Wilson? Flemish chemist Jean Baptiste van Helmont wanted to understand how plants gained mass. And he started an experiment in 1648 to figure it out. The experiment began with a five pound willow tree, 200 pounds of dirt and five years of time. Van Helmont only watered the tree in those five years with rainwater and distilled water. And at the end of the experiment, he weighed the tree, which had grown to a whopping 169 pounds. But when he weighed the dirt, he realized it had barely lost any mass. So his natural conclusion was that water was what gave plants mass.
9:55 Holly Frey? In 1699, physician and naturalist John Woodward used water from natural bodies of water, rivers and springs, to grow a variety of plants, including spearmint and potatoes, among others. His experiments with soilless plant growth identified the need for not just water for the plants to grow, but for specific nutrients. He came to this conclusion after he had grown the same types of plants, side by side, essentially replicating their environments, but giving one set distilled water and one set what he called non pure water. That was the water from the natural sources with no distillation or treatment. And this is really the beginning of the idea of testing water and soil
10:38 Holly Frey? and figuring out what was lacking for successful plant cultivation.
10:42 Tracy V. Wilson? Two German botanists working in the mid 19th century, conducted experiments that led to the idea of preparing mixtures of nutrients to be dissolved in water and added to the soil to optimize growth success. They essentially pioneered the idea of plant food in 1859. They also really established the idea that if you want to study plants, keeping them in water culture instead of soil is the way to go. Because that offered easier observation of the roots and greater control of the nutrients the plant receives.
11:18 Holly Frey? I also, in preparing this outline, left their names out for Tracy, but it's Julius von Sacks and Wilhelm Knopf. So those are the people that were doing that work. Coming up, we're going to jump forward in time a little bit to the 1930s and the man who is often called the father of modern hydroponics. But first, we're going to pause and have a little sponsor break.
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14:19 Tracy V. Wilson? Guess who's back in the house? The old gays return for season two of Silver Linings, their hit podcast from iHeart's Ruby Studio in partnership with ViiV Healthcare. Just wait until you hear what hosts Robert McMillan and Jessa have in store this time around. They strut back down memory lane, navigating life, love, loss, and everything that shaped them along the way. And as usual, someone just might break into song. From leather bars to bathhouses, dance floors to drag brunch, nothing stays off limits. These are the kinds of insights that can only come from experience. So listen to your elders, honey, and discover the silver linings you can take with you. All sass, zero filter, and decades of perspective from four friends
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15:25 Holly Frey? On March 1, 1937, Time Magazine ran an article that opened with the following, quote, "Last week, a new science was given a new name, hydroponics by its foremost US practitioner, Dr. William Frederick Garricki of the University of California. Set out in rows at the university's plant experiment station in Berkeley are a number of shallow tanks made of wood, concrete, metal. From some of these tanks grow thick towering clumps of tomato plants bearing rich red clusters of fruits. From other tanks, and in an equal state of vigor, grow potatoes, tobacco, gladioli, begonias. The roots of the plants are not in soil, but in chemically treated water."
16:09 Tracy V. Wilson? William Frederick Garricki was born in 1882 in Nebraska to a farming family. After high school, he attended Ohio State University and then Johns Hopkins to study botany. In the 1920s, he was working as a professor and researcher at the University of California, Berkeley, and it was while working there that he began serious research into raising plants without soil.
16:35 Holly Frey? Initially, Garricki called these projects "tank crops," and that use of the word "crops" was very deliberate because he was working to replicate the kind of yield that would normally come from traditionally planted ground crops. He was actually hoping for more. He wanted better yields from his hydroponics than ground crops could produce.
16:56 Tracy V. Wilson? So according to Garricki's account, there were three scientific challenges that needed to be solved to make growing plants in water alone work. One, it had to be simple and economical. Two, it had to move away from the preceding lab work, which focused on studying mineral nutrients alone. For soilless crop growth to work, it needed its own study focus, which had to also include fluid dynamics. He noted that water use in agriculture was physiologic only, but in soilless plant development, it was physiologic and dynamic, and its benefit to the plant was also dependent on how the water moved around the roots.
17:42 Tracy V. Wilson? And then, three, those water dynamics had to be formulated, meaning there had to be rigorous examination of the way a water-only approach to cultivation impacts the root systems and documentation of the different root development structures.
17:59 Holly Frey? As he developed his system, Garricki also sought to give it a name, and initially, he was calling it "aquaculture." But that was actually kind of a problem because that word was already in use. It has long been used to talk about growing aquatic plants and also even caring for marine animals. But according to Garricki, a colleague named William Albert Satchel gave him a good idea. He suggested creating a portmanteau from the Greek words for water, that's hydro, and labor, which is pono, so hydroponos, which Garricki then refined to hydroponics.
18:37 Tracy V. Wilson? Garricki would later write about the delicate nature of using just the right word for this "science", noting, quote, "Correct terminology is requisite to scientific progress. The incorrect terms which were used in attempts to describe soilless crop production before its scientific basis could be clarified have caused wide misconceptions of its principles and have markedly delayed the establishment of this method to wide use." He continued by mentioning other words that were used at various points and explaining why they were causing problems, quote, "Terms such as chemical farming, chemiculture, nutrient solution culture, and kindred expressions not only were inappropriate but
19:22 Tracy V. Wilson? did great harm to this development in its crucial formative period, as they created a wrong perspective concerning the scientific basis of soilless crop production. These terms projected the function of the nutrients into the foreground and thereby distorted their relative position of importance to other essential factors." He also noted that any of the terms that use the word agriculture, like soilless agriculture, were inherently incorrect because agriculture infers "land", which this "science" is purposely excluding. The word comes from the Latin word for "agir", which means "field", and "culture", I mean, cultivation.
20:08 Holly Frey? And Garricki was really successful in his efforts, and he shared his process with commercial growers in Northern California. Soon, a lot of farms were using his water-growing methods, and in turn, Garricki was getting data from their crops. That Time magazine write-up reported that Garricki was so loved by the growers who used his methods that he routinely received 500 pieces of fan mail a week.
20:35 Tracy V. Wilson? During his research, Garricki worked with Pan American Airlines to establish water-based crops at their refueling station at Wake Island. Wake Island sits in the middle of the Pacific Ocean, and in the early days of commercial aviation, when planes had to stop midway through a flight across the ocean to refuel, that was where Pan Am stopped. It was also where they would take on supplies for the next leg of the flight. But because of its position, it was impossible to have a fresh produce supply sent to the island. And there wasn't any soil on the tiny island that could have anything grown in it. But Garricki took a half acre of land and set up a hydroponic farm at Wake Island.
21:20 Holly Frey? Yeah, Wake Island often gets referenced as like, kind of the, the big proof of concept effort that happened in all of this. In 1945, William Garricki wrote an article titled "The Meaning of Hydroponics," which appeared in Science Magazine. And he described it in the opening this way. "Soilless crop production consists of growing crops in water containing chemicals. Large, shallow basins for the water and wood shaving, sawdust, straw, or other waste vegetable litter for seed beds which support the plants in the water are essential equipment. Water causes the architecture of the root plants to become different from those growing in the soil. These differences in architecture are reflected
22:04 Holly Frey? in the functions of the roots. For this reason, some crops can be grown more economically without soil than with soil, and by the same token, others cannot."
22:15 Tracy V. Wilson? He goes on to explain that difference in root architecture. It's for the sort of obvious reason that if something is growing in water, it can't anchor anywhere the way that it would in soil. Garricki explains it really clearly while also basing it in science that people are familiar with. Quote, "This change is according to a fundamental biologic law. An organ atrophies or changes in form and function in an environment in which some of its functions cannot operate."
22:46 Holly Frey? But though Garricki completely changed the entire field and really developed a lot of the principles that govern hydroponic gardening today, there are some questions about his relationship with Berkeley and the other scientists there. Even though he was employed at the university and some of these experiments were happening at the lab there, he claimed that all of his work in hydroponics had been done on his own time, and he refused to share any of his information or data with the school or his colleagues there. Garricki left Berkeley before he published his book, Complete Guide to Soilless Gardening. It was not as though UC Berkeley had not been interested in hydroponics. There
23:29 Holly Frey? seems to be disagreement about the work Garricki was doing and whether it was supposed to be for the school or for his own benefit. Either way, once he left Berkeley, the school assigned two other researchers to keep working on hydroponics and develop the work further. Those scientists, Dennis Hoagland and Daniel Arnnan, published their own book on hydroponics in 1938, Water Culture Method of Growing Plants Without Soil. It's possible to glean a little information about Garricki's relationship with Berkeley by reading the preface to his book. This does, to be clear, involve some speculation
24:10 Holly Frey? rather than clear evidence because no one is outright saying what their problems were, but there are some very specific things noted about how hydroponics research should and shouldn't be developed in Garricki's opinion. Quote, "Hydroponics can now be carried on without restriction by anyone who desires to do so. But scientific research on the subject must be safeguarded, the public must be protected from exploitation, and business interests must assume the responsibility for the development of the science. My own wishes are that research and educational institutions shall profit from the growth of hydroponics, that I shall be free to conduct research and teach the new subject without being responsible
24:54 Holly Frey? for business development, except in an advisory capacity where this is needed."
25:00 Holly Frey? Those private individuals who gave of their private funds to test the validity of new ideas and who provided the laboratory of practice wherein the dross of impracticability was removed from the hydroponic theory have earned the utmost consideration. They deserve the right to be consulted before any publication is made of results obtained by their plants.
25:21 Tracy V. Wilson? So it kind of sounds like he felt that the university was focusing on developing business ideas for outside entities rather than trying to simply sustain their own labs and research teams. And it sounds like he wants to be left alone by the school administration and not be bossed around in his lab. Garricki also lists the people and companies that contributed to his project, including his own family members and Pan American Airways, Inc., and the nurseries who donated plant stock. There's also the possibility that he had set up partnerships with people and companies as he was doing work that may not have been in his purview to do as a member of the school's faculty.
26:05 Tracy V. Wilson? In any case, the friction in play regarding his relationship with the school and his role in the sciences development seems to be referenced carefully in the pages of the preface.
26:17 Holly Frey? And we'll come back to Berkeley's side of the story in a moment, but then Garricki in this book makes a clear statement in the introduction just a few pages later that asserts that this work was his and his alone and that it was done despite a lot of people telling him his ideas were foolish. Quote, "Soilless crop production has captured worldwide attention. Thousands of inquiries have been received concerning it. My overflowing mailbox has not, however, been filled entirely with letters lauding the discovery of the world's newest crop production method. When I first announced that crops could be grown commercially without soil, the idea was received with skepticism by some and with outright derision by others.
27:01 Holly Frey? The work was done largely on my own time and with little aid from any scientific organization, notwithstanding requests therefore. Not until private businessmen offered their cooperation was hydroponics given a fair trial."
27:17 Tracy V. Wilson? A lot of the writing Garricki does in the book about hydroponics can come off as sort of conceited. He seems to dismiss historical hydroponic efforts as he mentions how strange it is that no one ever did it before. As the writing continues, it appears that he means at scale as a means to crop production. He notes that there have been some experiments with growing plants in water, but that they were all short sighted in that the goal is to improve the soil culture of plants, not to replicate crop production through a water nutrient culture. He notes, quote, "Scientists failed to realize the true value of a principle they themselves applied in laboratory experiments.
28:01 Tracy V. Wilson? The development of water culture as a means of studying the life processes of plants is covered briefly later in the chapter. It is enough to point out that plants have grown in nutrient solutions under experimental conditions for nearly a century. Modern scientific agriculture has been greatly aided by information obtained through these studies. By no means do I wish to disparage their value."
28:26 Holly Frey? Garricki also makes clear that it's actually kind of hard to grow crops this way if you don't know what you're doing. He mentions that you can't rely exclusively on formulas of nutrient solutions because there's just far more to successfully growing plants. He notes, quote, "Your success or failure in hydroponics will depend more upon skill in working out a proper technique indescribable in textbook language than upon possession of a simple chemical formula. You must combine to some extent the knowledge of the chemist, the botanist, and the farmer, arming yourself with an understanding of the fundamental requirements of plant life and developing through your own alertness and insight, a sure sense of the technique required."
29:12 Holly Frey? He also praises the insight of farmers for being able to manage all of the variables of light, heat, pest control, planting seasons, et cetera.
29:21 Tracy V. Wilson? One of the other big topics for Garricki in his book is conservation. He notes that, quote, "hydroponics will help us to conserve our natural fertilizers and to solve our future fuel problems. Of the fertilizers commonly applied to the soil, only nitrogen can be recovered completely. But in hydroponics, the plant food need never be wasted. The dry plants can be burned and the ashes used for nutrient solution. In this way, the so-called cycle of conservation has been completed for the first time." But he knows that for that to work and for hydroponic crop production to become standardized,
30:01 Tracy V. Wilson? that both farmers and the public have to be educated about the processes to eliminate misconceptions about it.
30:09 Holly Frey? So we mentioned that other publication of a book by Hoagland and Arnon that grew out of their work at Berkeley following Garricki's exit. And the introduction to that book is written by C. B. Hutchison, the vice president of the university and the dean of the College of Agriculture at Berkeley. His writing offers a different take on the very public-facing work of Garricki, and he kind of hints that he thought it caused problems, writing, quote, "In the 1930s, this development was given widespread publicity in newspapers, Sunday supplements, and popular journals. The possibility of growing plants in a medium other than soil intrigued many persons,
30:50 Holly Frey? and soon extravagant claims were being made by many of the most ardent proponents of the commercial use of the water culture method. Furthermore, amateur gardeners sought to make this method a new hobby. Thousands of inquiries came to the University of California for detailed information for general application of the water culture method to commercial as well as amateur gardening." Given that Garricki had also mentioned issues with charlatans getting in on the popularity of hydroponics, it's a little unclear if the extravagant claims that Hutchison refers to were those that Garricki also denounced, or if he's suggesting that Garricki's claims
31:31 Holly Frey? that hydroponics could outpace soil-based crop production is the extravagant claim he's referring to.
31:39 Tracy V. Wilson? Then Hutcheson goes on in a way that makes it sound like detractors who may not have believed Garricki's claim were the real reason that the university assigned two other scientists to the work. Quote, "Because of doubts expressed concerning many claims made for the use of the water culture method as a means of crop production, it became evident that an independent appraisal of this method of growing crops was highly desirable. I therefore requested Professors D.R. Hoagland and D.I. Arnon to conduct certain additional investigations and to prepare a manuscript for a popular circular on the general subject of growing plants in nutrient solutions."
32:21 Tracy V. Wilson? So this seems to hint at a friction between the school and Garricki was not just over whether he had done the work as a side project, but also involved the way he communicated with the press and the public about that work.
32:35 Holly Frey? The water culture method for growing plants without soil has become a foundational book for the science of hydroponics. But even that writing of Hoagland and Arnon seems to dismiss as outlandish the ideas that would eventually come to pass. Quote, "Widely circulated rumors, claims and predictions about the water culture production of crops often had little more to commend them than the author's unrestrained imagination. Grossly inaccurate in fact and misleading in implication, most of these claims betrayed an ignorance of even the elementary principles of plant physiology. For example, there have been statements that in the future, most of the food needed by the occupants of a
33:17 Holly Frey? great apartment building may be grown on the roof and that in large cities, skyscraper farms may supply huge quantities of fresh fruit and vegetables. One Sunday Supplement article contained an illustration showing a housewife opening a small closet off the kitchen and picking tomatoes from vines growing in water culture with the aid of electric lights. There has even arisen a rumor that the restaurants of a large chain in New York are growing their vegetables in basements. Stories of this kind have gained wide currency and have captured the imaginations of many persons." This cracks me up so bad. So.
33:58 Holly Frey? It kind of makes you wonder, did all of that friction at Berkeley kind of stem from all of these researchers simply not having the same vision of what hydroponics could be or become? Because so many of those examples that Hoagland and Arnon held up as outlandish have 100% come to pass. Rooftop gardens, some of which are fully hydroponic, have popped up in cities around the world. There are so many hydroponic setups for the home consumer that are designed to work in any room, even closets, using only a small footprint and artificial lighting. And a quick internet search turns up plenty of restaurants that are growing their own produce hydroponically.
34:41 Tracy V. Wilson? I laughed a lot as I was reading through this outline earlier and read that paragraph.
34:45 Holly Frey? They're like, this is ridiculous.
34:50 Tracy V. Wilson? We are going to pause here to hear from the sponsors that keep the show going. And when we come back, we will talk about the role of hydroponics in World War II.
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35:35 Tracy V. Wilson? Guess who's back in the house? The old gays return for season two of Silver Linings, their hit podcast from iHeart's Ruby Studio in partnership with ViiV Healthcare. Just wait until you hear what hosts Robert McMillan and Jess A. have in store this time around. They strut back down memory lane, navigating life, love, loss, and everything that shaped them along the way. And as usual, someone just might break into song. From leather bars to bathhouses, dance floors to drag brunch, nothing stays off limits. These are the kinds of insights that can Only come from experience. So listen to your elders, honey, and discover the silver linings you can take with you. All sass, zero filter, and decades of perspective from
36:17 Tracy V. Wilson? four friends proving that queer joy only gets better with age on the podcast that never gets old. Listen to Silver Linings, available on the iHeartRadio app, Apple Podcasts, or wherever you get your podcasts.
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37:47 Speaker 07 Livright, publishers of John U. Bacon's New York Times bestseller, The Gales of November, a chronicle of the S. S. Edmund Fitzgerald's 1975 shipwreck. Never has it been told better than by Mr. Bacon in this colorful book, writes John J. Miller of The Wall Street Journal, while author Hampton Sides proclaims that it's destined to be a classic. The Gales of November, now in paperback.
38:20 Holly Frey? Despite the bickering that seemed to be going on in a subtle way in the books of Garricki and his colleagues, it wasn't long before hydroponics presented a solution for the US Army Air Force during World War II. Also, just as a reminder, the Air Force did not become its own separate branch of the military until 1947. So, some air bases that were in use in World War II were just too remote or isolated to have access to fresh produce. The nutritional content of rations was pretty good in terms of balance, but it wasn't a substitute for fresh food. Additionally, the rations became really monotonous, and they weren't always super appetizing. So, in a lot of instances, soldiers skipped
39:04 Holly Frey? meals just because they didn't want to eat it anymore. Navy ships had the benefit of refrigeration units onboard to carry produce, but that was not always the case at bases. According to the Air Force Medical Service, "Flight surgeons started to be concerned about nutritional deficiencies among the men. Conditions like depression, night blindness, digestive problems, fatigue, and other issues that could compromise performance were all traced back to diet." In an air surgeon's bulletin from 1945, it was reported that, quote, "Medical officers in New Guinea as early as 1942 recognized the signs of dietary
39:45 Holly Frey? deficiency in military personnel under their supervision. Reports from other areas in which fresh foods were unobtainable indicated clinical evidence of vitamin deficiency in local diets with resultant fatigability and listlessness and even more acute symptoms in the personnel." The Aero Medical Laboratory at Wright-Patterson Air Force Base, Ohio, offered up the idea of hydroponic gardens as a way to get those crews fresh food. And that idea was approved. 14 hydroponic facilities were planned by the US Army Air Force, although they weren't all completed before the war and the program ended.
40:26 Holly Frey? But in the places that those facilities got up and running, they were pretty prolific. One facility on Ascension Island, which sits in the Atlantic between Africa and South America, needed to distill fresh water from seawater for their setup. It also required the hand pollination of crops because there were no bees on the island. This was not the only facility to deal with that particular challenge, and there were other challenges that popped up depending on location. In a lot of places, they had to ship in bees. Some of the facilities in the Pacific had to really aggressively combat insect infestations. But this project ended up being really successful.
41:07 Holly Frey? The Ascension hydroponic garden produced nearly 5,000 pounds of produce in a single month, which included lettuce, cucumbers, peppers, and radishes, among other vegetables. Even after the war, some of these facilities were kept running for a while until the program was shut down permanently.
41:26 Tracy V. Wilson? But even after all of that, there was still some naysaying about hydroponics. In the 1947 Yearbook of Agriculture, published by the U.S. Department of Agriculture, Neil W. Stewart, a physiologist from the Bureau of Plant Industry Soils and Agricultural Engineering, writes, quote, "The idea of growing plants in water or sand without soil has fired almost everyone's imagination at some time or other. Whether it is called hydroponics, soilless culture, water culture, nutriculture, or whatever, many an American has dreamed of using it to become rich or self-sufficient when he gets out of the army, or retires from the office, or gets his little place
42:11 Tracy V. Wilson? in the country. But the truth is that soilless culture, a practice of great value to students of plant nutrition, has been over-publicized and over-popularized so that many persons have false impressions as to its real possibilities and limitations." Stewart goes on to explain that people just don't understand water culture and that issues like aeration and physical support for the plants are major drawbacks.
42:39 Holly Frey? So many of these write ups to me sound so, I don't know if I would call it gatekeepy or conceited on the part of scientists who are like, "The average person just can't understand the idea that you need a pump involved." It's like, this isn't rocket science, y'all. I don't have to do formulas, it's fine. Stuart then explains the various techniques of hydroponic gardening and crop production to remedy the various false impressions that people may have. And then he concludes with a prediction about the future of the practice, which sounds pretty positive. Quote, "Some technical training and considerable experience are necessary for the efficient management of soilless culture crop production.
43:21 Holly Frey? Its future development in the United States will probably be confined to the production of crops having a relatively high unit value: ornamentals, out-of-season vegetables, or seedlings for transplanting. Under favorable conditions, yields may be expected to equal or surpass similar yields in soil, but so far, the differences have not been outstanding. The method is also well-adapted for specialized studies in plant nutrition, phytopathology, and plant breeding, where growth under standard conditions is desired. The indications are that soilless culture techniques will be more widely employed in the future."
44:01 Tracy V. Wilson? After World War II, there were commercial growers who became more interested in hydroponics. The floral industry saw a number of nurseries adopted, and some large-scale greenhouse operations also emerged. Then in the 1970s, General Mills made a lot of headlines when it announced that it was going to launch what the press called "a vegetable factory."
44:23 Holly Frey? Yeah, they developed a whole system where they were producing vegetables indoors and were marketing them in that way, as an effort to try to help boost, one, their production and thus their profits, but also like to get people excited about this idea of a way to grow fruits and vegetables. And then- In 1982, hydroponics got a huge boost in visibility thanks to Epcot in Walt Disney World when it opened the Gardens of Tomorrow exhibit at the Land Pavilion. And the Land Pavilion showcases still a variety of hydroponic growing techniques,
45:06 Holly Frey? and guests can see a variety of plants thriving in the indoor facility. There, you can either take the boats that are the standard ride, or you can do a behind-the-seeds tour and walk through and get all kinds of extra information. Highly recommend if you're a plant person. The vegetables and fruits that are grown there are actually the ones that are served to guests at the various restaurants on property.
45:28 Tracy V. Wilson? Since then, the science of hydroponics and the desire to embrace it have grown in a world where there are increasingly dense populations in places that don't offer a lot of available land for growing food. Hydroponics and other soilless growing systems continue to be developed and researched in the hopes that in a world of shifting and shrinking resources, we can continue to find ways to feed people. NASA has had research projects in hydroponics for years, starting with the first vertical farm in the United States, which was assembled inside a decommissioned hyperbaric chamber that used to be used to test the Mercury Space Capsule.
46:10 Tracy V. Wilson? NASA continues to be a significant leader in the field, and a lot of commercial farms today have benefited directly from innovations in the field that were developed by NASA.
46:21 Holly Frey? And of course, now you can go out and buy your own hydroponic system from a variety of options. The global hydroponic market is expected to be worth $16 billion this year. That's the briefest version of the history of hydroponics, which I'm obviously obsessed with at this point in time.
46:44 Holly Frey? I have yet another email about Advent calendars. Look, I'm just focusing on things that bring me joy. This one is from Rebecca, who writes, "A message from the perpetually behind. Just finished the December 2023 episode on Advent calendars. You mentioned homemade ones, so I thought I would share mine. My mom made felt wall calendars for my brother and sister while pregnant with my brother, who was due near Christmas. My sister was four. When I, the surprise baby, came 18 months later, she had her hands too full to get back to making me one for a number of years. So I actually helped her make mine when I was about 11." I love this. Rebecca goes on to say, "We were never religious. My dad referred to himself as a recovering Catholic, and my mom was raised Southern Baptist,
47:29 Holly Frey? but became an atheist. But she adored all of the traditions and pageantry of Christmas celebrations. As far as I know, Advent calendars were not a tradition in either family. I suspect it is something that she saw in Woman's Day, or BHG, or one of her craft magazines. She made my siblings' calendars circa 1972. It's a basic Christmas countdown with a five-by-five grid, so it includes one for Christmas Day. Each day, you would move the piece from the grid up to the top. Mine has a stocking, my brother's was a sleigh, and my sister's a tree. Traditionally, we would move the piece right before bed, so it would be the last act of Christmas Day to put up the last remaining piece. All of ours had a Santa for Christmas Eve and a Christmas tree for Christmas Day.
48:14 Holly Frey? The other pieces varied and were personalized. My sister loved angels, so hers included one. My brother's had a cake with candles for his birthday. Mine has a cat because of my love of them. Some of the pieces are the originals my mom made almost 40 years ago. Others are more recent replacements I made. My grown-up embroidery skills were used for the snowflake and doll's braided hair. I still put it up every year. This year, I even took it with me and put it up in my hotel room when I traveled for the holiday. I hope you enjoy the pictures and maybe feel inspired to try making one of your own. I've considered..." Making a pocketed one with a different design on each pocket that you could then customize with your own treats like chocolates or teas or mini liquors.
48:58 Holly Frey? FYI, while visiting my friend for Christmas, I found out Bun Mama has a jam jelly advent calendar, totally getting one next year. I've had that calendar. It's good. This is the cutest thing in the world and I love it and I love family traditions that go on for so long. And seeing all of these adorable little ornaments you add to your advent calendar is precious. I love it so much. There's a little black felt kitty cat on this one that Rebecca sent pictures of that it's just a simple outline of a kitty, but I love it so much. It's precious. Thank you so much for sharing this family tradition with us. It's very joyous and brings me a lot of delight. If you would like to share pictures of your Christmas decor, I don't care what month it is, you can do that in July if you want
49:43 Holly Frey? Halloween year round, Christmas year round. I don't mind any of it. You can do that at [email protected] . You can also subscribe to the podcast on the iHeart Radio app or wherever you listen to your favorite shows.
50:02 Tracy V. Wilson? Stuff You Missed in History Class is a production of iHeartRadio. For more podcasts from iHeartRadio, visit the iHeartRadio app, Apple Podcasts, or wherever you listen to your favorite shows.
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51:19 Holly Frey? A rare disease diagnosis can change your life, but it doesn't have to define your future. In season seven of Untold Stories: Life with a Severe Autoimmune Condition, host Martine Hackett continues the conversation with people living with MG, CIDP, and the broader rare disease community, exploring what comes after diagnosis through stories of hope, progress, and connection. Produced by Ruby Studio in partnership with Argenx, listen on the iHeartRadio app, Apple Podcasts, or wherever you get your podcasts.
51:53 Speaker 07 Livrite, publishers of John U. Bacon's New York Times bestseller, The Gales of November: A Chronicle of the S.S. Edmund Fitzgerald's 1975 Shipwreck. "Never has it been told better than by Mr. Bacon in this colorful book," writes John J. Miller of The Wall Street Journal, while author Hampton Sides proclaims that it's destined to be a classic. The Gales of November, now in paperback.
52:20 Speaker 00 This is an iHeart Podcast. Guaranteed Human.
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