In the summer of 1975 I started experimenting with aeroponics. I was encouraged to do this by Buckminster Fuller (the American inventor and futurist) and his British friend Stafford Beer (a pioneer cyberneticist). 

In the summer of 1975 I started experimenting with aeroponics. I was encouraged to do this by Buckminster Fuller (the American inventor and futurist) and his British friend Stafford Beer (a pioneer cyberneticist). Both Beer and Fuller believed that there was an urgent need to improve the performance of global agriculture, particularly in terms of its resilience, sustainability, affordability and productivity. In his book, Utopia or Oblivion, the Prospects for Humanity, published in 1969, he wrote about humanity’s “Final Examination” which he defined as “a soon to-be-experienced period of acute social and environmental disruption, which will determine whether humanity will be able to fulfill its purpose in the universe”. Both Fuller and Beer believed “environmental disruption” would soon threaten the lives of billions of people around the globe and new ways to counter that threat should be developed and tested as soon as possible. Beer drew up a list of performance requirements for an optimised system for growing staple food crops virtually anywhere on Earth at any time of year. It was a long and challenging list, which initially I regarded as being hopelessly idealistic. However, Fuller and Beer - mainly the latter - made a number of suggestions about how I should tackle the problem. These have proved pivotal to the development of the ‘Airponix’ aeroponic system.

One of Beer’s most useful contributions to the project was his suggestion that I use decision theory to help guide development. Fuller from the outset was adamant that an important performance requirement was missing from Beer’s long list, and that was that the system should be as lightweight as possible. Beer’s initial reaction - a facetious one - was to suggest I base my project on growing crops in air. But then Beer told us about seeing plants in South America called epiphytes. These are plants that grow harmlessly on other plants (such as trees) or surfaces which derive their moisture and nutrients from air, rain and debris accumulating around them. He also told us that there are well over 15,000 types of epiphyte in the tropics alone, and over 30,000 worldwide as well as numerous uncatalogued species. On hearing this Fuller then told us about his experiments with a fog-making device (he called it a Fog Gun) dating back to 1948 when he was teaching students at the Chicago School of Design. He then suggested I use nutrient-containing water fogs to grow crops in lightweight plastic film enclosures. By that time Beer had become enthusiastic, and said that if thousands of varieties of epiphyte can flourish with their roots in the air there was no apparent reason why food crops couldn’t flourish in artificial controlled environments.

When I told my friend John Chadwick about this conversation and my plan to test Fuller’s idea for growing crops in fogs in plastic film enclosures, he offered to contact his Californian friend Dr Thomas R Mee who was an expert on water fog and how to make it. Tom Mee’s company Mee Industries Inc. supplied and installed their fog making system for protecting vineyards and citrus plantations against frost damage. I used Mee impact pin fog nozzles on all my aeroponic experiments. 

I began my aeroponic experiments in my parent’s garden on the Isle of Wight. Initially I cut and welded sheets of black and clear 200 gauge polyethylene film to form 30 foot long tubes. This dimension was determined by the size of my parents former stable yard. The tubes were divided into two sections - similar to a double-barrel shotgun on its side. The upper section with a clear film “roof” (for containing foliage) was divided from the lower all black film section (for containing roots) by a horizontal sheet of black film. The first tube was intended to demonstrate that the concept of inflated film tubes worked reliably - no seeds or plants were involved at this stage. Equipment reliability is vitally important in aeroponics because without the buffering effect of soil moisture plant roots can die in under 10 minutes in warm weather.

The welding process involved using a modified soldering iron with a steel horn-shaped tip. To prevent the hot horn tip sticking to the melting plastic films aluminium foil was laid over the film before the tip contacted the foil. The aluminium foil didn’t adhere to the molten films so could be reused many times. The process was effective, but slow and tedious. 

Both upper and lower tubes were inflated by low pressure air supplied by the ventilating fan which blew fog along both tubes. Fog was supplied to both leaves and roots simultaneously. The fog was intended to provide a cooling, humidifying and foliar feed action in the upper tube, and a root feeding/watering action in the lower tube.

The fog was made using a pump producing 200 p.s.i.. The pumps available at that time in the UK had a far higher capacity than my group of four Mee nozzles could cope with, so a high proportion of the water and its dissolved nutrients had to be recirculated to a water tank. After about 30 minutes of operation the temperature of the water in the tank would build up to the point where the nutrient started to separate out from the water and form a brown scum floating on the surface of the water. This problem meant I had to use a much larger water tank. This and other equipment problems were eventually overcome, but prevented me from starting to grow a crop that first year.

With no one else’s experience to guide me I had to find a way to position seeds on the horizontal plastic sheet which separated the upper tube from the lower one in a way that would allow them to germinate and support the growing plants until they were ready for harvesting. After testing about a dozen different designs I ended up with one that suited the first crop - lettuces - I planned to grow. Each seed was placed centrally on a 2 inch diameter disc of soft toilet tissue, a 1 inch diameter ring of latex glue was then applied around the seed and a second disc of toilet tissue then placed over the first one, trapping the seed between them. The resulting “seed packet” was then ready to place over its respective hole - about the diameter of a pencil - in the horizontal plastic sheet. The heated welding iron was then pressed onto the perimeter of the paper seed packet welding it to the plastic sheet below and forming a seal. 

In the early summer of 1976 I made a 30 foot long tube containing 40 equally spaced seed packets each one containing a single lettuce seed (lettuce variety Tom Thumb). The timer controlling the pump supplying water to the fog nozzles broke down on the first day of the experiment, so I had  to operate the pump manually for a further 21 days. By the end of that period, - largely due to a continuous spell of fine warm weather and the fact that the lettuce were a dwarf variety - they were ready to harvest.  The 22 day period was roughly half the normal commercial growing time. The nutrient I used was a concentrated liquid plant food developed for commercial nutrient film technique (NFT) hydroponic systems. I don’t have details of the specification or the name of the manufacturer. It’s worth mentioning that shortly before the experiment was switched on my younger brother Peter - a professionally trained farm manager - inspected the deflated length of finished tube and told me that it was doomed to fail because shortly after the lettuce had developed leaves the high humidities would create ideal growth conditions for a common type of grey mould called botrytis which would soon kill them. Having spent so much time and effort making the tubes, obtaining equipment and setting up the experiment, I decided to run it anyway. To my surprise, and especially my brother’s, there was no sign of botrytis on any of the 39 lettuce (one of the seeds failed to germinate) which looked and tasted entirely normal.  The reason for the missing botrytis I still don’t understand. My brother attributed it to a combination of negatively charged fog, long periods of very high humidity and near continuous rapid air movement. On the strength of that first experimental result I filed my first aeroponic patent: UK Patent No. 1600477 in 1976.

Potatoes and tomatoes
During the last week of my lettuce experiment when it was clear it was working well, I used the time to make more plastic film tubing for a second aeroponic experiment. This time growing potatoes because of my wish to discover as soon as possible if a staple food crop could be grown aeroponically.  About a fortnight after the lettuce experiment ended I switched on a 30 ft long tube roughly three times larger in section that the lettuce tubes and about 4ft high. The main differences between the first experiment and the second one was that only the plant roots were enclosed this time and in an A-frame structure made from bamboo rods with black plastic film draped over them and secured to the rods with sprung clips. Each bamboo triangle rested on the courtyard cobbles and was spaced about 4ft from the next one. Each seed potato (variety Maris Piper) was supported on and covered by blackened (to make it as opaque as possible) soft toilet tissue carried in a plastic net taped over a 3 inch diameter hole in the plastic film.  The potato plants grew rapidly and by week 12 many of them carried potatoes large enough to start picking. I left smaller tubers on the roots to continue increasing in size and kept picking until week 16 when there were still many small tubers still growing in size.  A couple of weeks after the experiment was switched on it was obvious that the potatoes were growing rapidly. When I reported this progress to my brother (he was living and working on the mainland) he suggested I include some tomatoes in the experiment which he told me were related to potato plants and so should respond equally well. I took his advice and substituted a couple of young tomato seedlings in plastic net pots for a couple of sprouting seed potatoes. The two tomato plants flourished and produced good crops of cherry tomatoes. What variety they were I can’t recall. The owner of the plant nursery which had supplied the two tomato seedlings showed keen interest interest in this result.  
The potatoes produced had the usual Maris Piper oblong appearance, except they were unmarked, and completely clean. They weighed about 8 oz each. The 38 plants produced a total of about 200lbs of top quality potatoes suitable for baking, and would probably have produced at least 25% more if I hadn’t stopped the experiment in week 16 when I had achieved my objective of proving potatoes plants can flourish under aeroponic growth conditions. On this occasion they had done so without needing to use any fungicide, pesticide or, of course, herbicide.   

An interlude 
In 1981 I moved with my family to Houston, Texas, where I worked for a local energy company subsidiary, the Texas Energy Investment Corporation (TEIC) for two years. Through my work there I came into contact with NASA, Houston which at that time was experimenting with aeroponics as a way to feed astronauts with fresh produce on their way to and from Mars - as part of NASA’s first Mars Mission Study Program. One of the principle reasons for their interest in aeroponic systems was their low weight, so Fuller’s concern to see the development of lightweight ways to grow food plants was prescient. NASA were only interested in small scale aeroponic systems, but I had several very useful meetings with their in house plant physiologist Dr Allan H. Brown who was running their aeroponic research programme, and showed keen interest in my experimental work on the Isle of Wight. He was convinced aeroponics had an enormous future and thought it offered great potential for developing enhanced growth techniques used in  combination with low-cost controlled environments that would increase food crop yields dramatically without compromising food quality.

I returned to the Isle of Wight in 1982 and encouraged by my very positive NASA contacts decided to resume work on my aeroponic experiments. I wanted to scale up my next set of experiments which meant having to find a larger space than my parents garden. I contacted the local plant nursery - Kings Nursery - which had supplied me with the two tomato seedlings several years earlier. To my amazement the owner - Leo King - offered to not only provide the space I needed, but also to set up and run the experiment at his cost! The only stipulations were that he would only grow strawberries aeroponically and that if successful the crop was to be sold commercially. I readily agreed and his staff soon set about building a 100 ft long styrofoam panel-covered timber A-frame inside an empty polytunnel. He made holes in the styrofoam A-frame in which he inserted 200 strawberry seedlings in moss set in plastic net pots, installed a variable speed extractor fan at one end of the A-frame and at the other a timer-controlled pump and a set of fog nozzles. The system used the same type of nutrient I had used in my earlier experiments and it ran for three months. It produced a heavy crop of good quality strawberries. Picking started in month two. The variety grown was Royal Sovereign, an old English strawberry variety usually grown for its flavour rather than its yield.

Past Data and aeroponic slide commentaries

I need to mention that most of the files and slides containing information about my early aeroponic experiments were destroyed in a flood so these are some of the few that survived.

1975 - day one - Inflated tube
1983 - week 3, lettuce seeded tubes at Warninglid, West Sussex, UK. Gawain Baillie trial which shows high pressure pump in the foreground. [The pump used on all my aeroponic experiments was made and supplied by HPC Precision Engineering, of Burgess Hill, West Sussex, UK. Note: our new nozzle concept should have minimal pressure drop thus such a high pressure pump will no longer be required, resulting in significant cost reductions and improvements in reliability compared to current systems]

airponix briefhistory 01

1983 - External view of the partially A-frame at Kings Nursery
1983 - Week 1, day one, the day the Kings Nursery system was switched on

airponix briefhistory 02

1983 - Week 9 – Pick Your Own from Kings Nursery aeroponic strawberry crop over had A-frame growth chamber where fog is introduced. Nozzles cooled plants in hot weather.
I took these detailed photos because the foliage at this end for about 10 feet was a darker green than the rest of the 100 ft length and the leaves were significantly larger than on the other plants further away from the fog nozzles. This difference was attributed to an effect on the newly formed fog droplets [Note: Phenominen just been being patented - I don’t yet know if this assumption is correct but we hope to test this in the next testing phase/trial, along with other ‘enhanced growth technologies’]. The manager of the nursery assured me all the plants were the same Royal Sovereign variety - they hadn’t grown any other variety for many years.

airponix briefhistory 03

Airponix aeroponic system technology readiness levels (TRL)

TRL ONE - Basic principles - The system offers considerable growth enhancement potential under the following 8 headings: 
Electrical growth stimulation - using electrically charged (positively and negatively charged fogs) to leaves and roots.
Hyperbaric effect- slightly raised air pressures
Micron and submicron fog droplet foliar feeding
Time controlled and pulsed red and blue LED lights
Air speed - leaf surface air boundary layer reduction
Carbon dioxide air enrichment
Growth promoting rhizobacteria applied to roots
RNA growth modification

Each of the above growth enhancement effects have been observed and recorded to greater or lesser degrees, some a long time ago. For example, electrical plant growth stimulation - now commonly known as electroculture - was first investigated in the middle of the18th century by Dr Mainbray of Edinburgh in 1746. There have been many demonstrations of the positive effects of electricity on plant growth - including potatoes - since that time right up to the present day. None of those discoveries have been commercialised because they were either produced under laboratory conditions that couldn’t be applied in the field, or in situations where the electrified plants grew in soil. The lack of control, equipment costs and complexity have always deterred electroculture progress. The Airponix system by using electrically charged fogs presents a unique set of opportunities for overcoming those historic electroculture limitations.

TRL TWO - The basic principles of aeroponics are well understood and are now commonly used commercially, but usually for salad crops, herbs. For example, Goldman Sachs in four transactions between 2013 and 2015 secured $30 million in funding to finance the first two phases of a project to redevelop a 69,000 square foot industrial building located in Newark’s Ironbound neighbourhood. The proprietary aeroponic and LED lighting technologies used will allow its urban farms to grow up to 22 crop turns per year, compared to three turns per year via conventional methods. The systems require no pesticides and use 95% less water than traditional farming methods. The proprietary aeroponic technology to be used is no further advanced technically than the one I was using in 1983.

TRL THREE - My aeroponic R&D was first activated in 1975. 

TRL FOUR - My system has always been tested under field conditions, never in laboratories.

TRL FIVE - All equipment, pumps, fog nozzles, timers, humidistats, thermometers, variable speed fans, etc., were off-the-shelf components. The only bespoke items were the plastic film tubes, the timber/foam plastic growth chambers and the ways materials and net pots were used to hold seeds, seedlings or mature plants (and their crops) in place.

TRL SIX - All of the four plant types I grew in my aeroponic experiments - lettuce, potatoes, tomatoes and strawberries flourished - except when there were equipment failures or power cuts.

TRL SEVEN - In my potato/tomato and strawberry experiments I used A-frames instead of the inflated tubes I started with because when they collapsed due to the air supply cutting off they were difficult to re-inflate - unless the fan used was about three times more powerful than it would normally need to be. Today I would use plastic films draped over tensioned ropes so the growth chambers are always clear of the ground (to prevent rodent attacks) and can quickly and easily be raised or lowered. I tested this resilient, in both senses, tension design - with inputs from Surrey University’s engineering department - at Kent Science Park in 2015, and it worked well.

TRL EIGHT and NINE - The last of my aeroponic experiments was in 1983 when a 100 ft long A-frame grew a heavy crop of strawberries. I don’t know how its yields compared with the same variety grown conventionally as a control, because the owner of the plant nursery was unable to resist selling them as a pick-your-own (PYO) crop.  It was popular with pickers, most of them elderly (a high percentage of the Isle of Wight’s population are retired) because they didn’t have to stoop to pick the fruit, it was clean (i.e. they didn’t come across any snails) and the ground was dry.

Many of the PYO customers, particularly the elderly ones, returned several times. In other words the experiment was a complete technical and commercial success!