Growers Network Staff

February 2, 2019 19 min read
February 2, 2019
19 min read

Ask Me Anything with Ethan Kayes

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Growers Network recently hosted an Ask Me Anything with Ethan Kayes, a thought leader and floriculturalist. We have truncated and transcribed the content for your perusal! If you are interested in joining these conversations, consider Joining Now.

In a new segment, we are bringing you our Ask Me Anything from the community! Our AMA’s were previously only available on the Growers Network Community, but we want to give you a chance to see the high-level conversations happening in our forum. Enjoy!

This Ask Me Anything was hosted by our Community Manager, Nick Sandberg.


  • GNS – Growers Network Staff
  • Ethan Kayes – Our guest host
  • GN Member – A member of the Growers Network Community

Editor’s Note: Sections of the conversation have been moved or clipped out for clarity. Because our AMAs are living, breathing conversations, you can get people talking over and around each other. We have done our best to clarify people’s conversations without putting words into their mouths.

Skip to any section in the AMA:

About our Guest

I am a retired horticulturist [who earned] my bachelors [in] ‘87 and masters degrees [in] ‘89 from the University of Missouri Columbia. I wanted to [earn] my PhD, [and] I even had a topic picked out: Fecundity index modeling of pest to predator populations in homogeneous environments. But, I felt [that] I needed some real life experience before pursuing an even more advanced degree.

Real life happened.

I ran a cut flower greenhouse in Kansas City for five years. We worked 7 days a week 365 days a year. [My wife and I] had a baby and needed to offer our bundle of joy more time with his parents. I was [eventually] headhunted by a Fortune 50 technology company to lead up special computer language projects. One third of my time for twenty years was spent reading research journals in order to solve real business problems. I found many simple solutions to very complex business problems and often the solution came from very unlikely sources.

One last note about me. I was forced to retire because of a genetic health reason. So I live off [of] a fixed income. However, I am willing to share my knowledge and I am willing to research just about anything.

Editor’s Note: The genetic condition Ethan references affects his ability to type. I have done my best to improve the readability of his messages without changing the message.


Ethan: Thanks to everyone for inviting me to speak. Old people still have good ideas!

[Here are some] topics that I am very interested in discussing:
  • Genetics in cannabis production
  • Technology and its role in making us better growers.
  • IPM in our SOPs [and] how can we simplify our procedures.
  • [How] our accounting departments should be an asset in our grows.
  • Defining a standard unit of measurement in cannabis production
  • Basic plant nutrition and plant physiology in cannabis
  • Fact vs fiction in Cannabis production.
  • Who will be the money makers in the cannabis industry of tomorrow?
  • What can we learn from the WW2 Hemp for Victory that can be applied to the cannabis industry [today]?
  • Research trends in cannabis production and research in other fields that can make us better growers.
  • How some grow lighting manufactures are letting us down.
  • Why do I say “From the voices in my head” and why do I only work for pairs of socks?

How will cannabis be legalized in Europe?

GN Member: Yeah, Ethan is [the] best guy for [an] AMA, he has great knowledge and experience.

Ethan tell me how you think cannabis will be legalized in Europe?

In my mind: It’s very hard to do this in Poland. Hemp is supposed to be legal, but [any] THC excretion >0.2% effectively hinders anything except typical industrial use. It’s terrible in my opinion.

Ethan: I don’t know how [or when] cannabis will be legalized as a recreational drug in the EU. As a fiber crop we are [already] there. [I expect that] if the US legalizes recreational cannabis, the EU will not be far behind. Or, it [may] happen the other way.

I worry that hemp will solely be [seen as] a commodity. This will shove small producers out of the market, and Big Ag will control the fiber industry.

GN Member: I was not just talking about marijuana strictly, but about the entire industry related to it. [I should have] used the term hemp. The law is too restrictive, […] and it is really killing the production of hemp.

Ethan: Adam, I think in North America [the term] Hemp will [be used to] refer to fiber production. Cannabis will be [used to] refer to high THC production.

The problem is that they are the same plant [species]. I think Cannabis sativa is the primary plant species, and Cannabis indica is really just [modified] sativa. Cannabis afghani is its own species, but can [be] crossed with C. sativa. Cannabis afghani is a high THC producer and has long internodal fibers, but is very short, maybe a meter tall. I think we get the hemp we grow [today originated] from a cross between cannabis sativa and Cannabis afghani as a byproduct of First Anglo-Afghan War, because we see the first modern hemp [appear in records] after 1842 in India. It very quickly made its way to Europe and North America. I also think that this is [where the name] Cannabis indica originates. The herbarium specimens [we] see are collected from India in the 1850’s. Prior to this, we only see “hemp” referenced as oil hemp. The seeds made a good lubricant and lamp oil. The fiber was an ok quality kind of like flax. Once Indian hemp made it to North America, it became the dominant fiber crop. But [it] was not an abundant seed producer like the older varieties.

Varieties of Cannabis sativa [like] “Finola” were bred in Finland between WW1 and WW2 as a good fiber crop [for] northern climates. It is not very good in high temperatures. The dominant varieties of hemp in the US are very heat-tolerant and have a propensity to produce high-THC children.The Finola variety does not [tend to] have high-THC children.

We mostly want good THC producers, [and] I think [that] terpenes are closely linked to [the] color pigments in cannabis. So if you want flavor(s), you breed for color. And if you want a drug, you breed for THC. What is interesting about this is that] the heavily pigmented varieties [of cannabis] have some of the highest THC content.

How do you scale up a cannabis grow?

GNS: How do you scale up a cannabis grow?

GN Member: Our little ten-acre ornamental greenhouse in Oklahoma is the last of its kind in our state. At ~500,000 sq. ft. We rank about 110th or so on the annual list of greenhouse size in the industry. We are very interested in scaling our current 30,000 sq. ft. cannabis greenhouses to 2-5 acres.

Ethan: I don’t think that there any secrets in good growing. Cannabis is really no different than other floricultural crops. There are some tricks in growing great cannabis, just as there are some tricks in growing good [chrysanthe]mums.

The problems in large scale cannabis production [stem from] IPM and post-harvest handling of the crop. The list of EPA approved chemicals for cannabis is very small, and this change [can be difficult] for most floriculture operations. [It’s a challenge to switch to] very strict IPM practices as part of [your] SOPs. However, I think floriculture operations [could] benefit from the changes, and you will see lower operating costs as a whole.

[On a related matter], measuring costs by square foot week of production is not granular-enough detail for cannabis production. I think [the ideal unit of measurement is] grams of dry weight per square foot week. This [will require] some operations to change their accounting systems to reward good production practices and penalize bad practices. It is much more important in cannabis production to be proactive than reactive.

The other [significant] change [as you scale up] will be your choice of growing mediums. Large soil mixes for nursery production are most likely the best choice for a grow. The container size for Cannabis production is closer to nursery production than traditional floriculture.

GNS: I love this quote (there are no secrets in good growing) and I agree wholeheartedly! Gone are the days of “trade secrets” in the cannabis industry!

Ethan: I was told [that] the biggest secret to being a good grower is walking [through] the crops 3 times a day with a note card.

How did you get started in floriculture? How did you get into cannabis?

GNS: How did you get started in floriculture? When and how did you first discover cannabis?

Ethan: My father was an MD and my mother was a Ph.D biologist. I hated medicine, [but] I really loved plants and mushrooms.

Cannabis was what kids my age did. I just [happened to] do it more than my friends. I think I was trying to self-medicate. My friends and I would collect skunk along the old Katy train lines in St. Louis.

When I went to the University of Missouri, I found their horticulture program. They let me concentrate on what I loved: Growing plants. I particularly fell in love with cut flower production. I particularly liked Lathyrus odorotus and found a niche in the market for locally-grown cut flowers. Winter production was great, but summer sucked.

[As for] cannabis production… well there was a lot of illegal production in my teens and twenties. I stopped when [my wife and I] had a child. But I grew a lot of pot in that 10 year period. We were fortunate to not get in trouble.

GN Member: I ran the other road. [I was] born into a guerrilla grow family in NorCal. But that’s a story for another time. You have done amazing work. And it continues here. We are blessed to have you.

GNS: I couldn’t agree more! Thanks for being here, Ethan target=_blank>@Ethan! Cheers!

You were visited by the DEA?

GNS: How long did you actively practice floriculture as a profession? In our past conversations, you told me the DEA visited your greenhouses on several occasions… can you elaborate a bit about that? What were those federal visits like?

Ethan: I actively grew floriculture crops from 1982 through 1996.

We would see the DEA at our greenhouse about twice a year, sometimes more often. They just wanted to know if anyone was trying to buy commercial horticulture products from us. [We would] walk through the greenhouse and give them coffee and some seconds of cut flowers.

For this level of cooperation, we [were granted] access to confiscated greenhouse supplies. We purchased a lot of lights for 10 cents on the dollar, and HPS bulbs were essentially free. I think I bought two cases of MAH bulbs for like $5 dollars — 48 bulbs for $5 dollars.

GNS: When I worked in finance, occasionally the SEC would visit. Our office manager had a procedure that involved locking them in the boardroom, showing them the files, then slamming the thermostat as low as it would go. Your procedure with the feds sounds way friendlier! Sounds like you ended up with some nice perks though!

Ethan: I had a great deal more exposure to the government and regulations working at AON Hewitt. At the end of my working career, I was one of five people who could see the unmasked data for about 1/3 of the US population, [including] SSN, salary data, address, health data, [and more]. I was responsible for creating blind datasets for our actuarial group and our compliance divisions. All of our data was so encrypted, [and] I was worried [that] the guys with master [encryption] keys would get hit by busses.

How did your experience with floriculture help you with computer science?

GNS: Did you find that your background in floriculture served you as your career path veered into computer science? Also, it’s remarkable that progression software has made its way into the horticulture industry! Where do you see the future of cannabis cultivation as we see more synthesis of tech meets growing?

Ethan: In the following areas:

  1. First, the grow itself for environmental controls. Every environmental control down to watering your plants [will see more tech].
  2. Second is going to be accounting [that] supports the grow. This is a tech issue because we need a non-invasive way to record tasks performed by people in accounting.
  3. Third, we [have] reached the point where we have enough big data sequencing cannabis DNA that we can figure out progressive breeding programs. This is going to lead to the holy grail of seed-produced female F1 plants. This [will] cut our production costs dramatically.
  4. Last technology is going to allow us to quantify potential secondary compounds that any given cultivar can produce. We will be able to see how our grow measures up to other grows. My feeling is [that] the people who can produce the most root hairs as a percentage of dry weight are going to win.

Are water quality issues being addressed?

Ethan: The industry is moving to a lower pH than I am used to growing in. This will be a hard change to make for me because I have to learn a whole new set of availability numbers. Water in Oklahoma is evil. [It has a] high pH with one hell of a lot of buffering. I suspect that growers in the Midwest [will have problems] that are different than growers on the east and west costs. Water management in the Midwest is just harder.

Kansas City water was like having rocks flow out of the pipe. The water was so hard and had such a high pH that we were forced to use phosphoric acid in our main irrigation lines. This forced us to account for phosphorus in our grow. All the off the shelf feeds had to be adjusted to compensate for the phosphorus in our irrigation water. We also had to rebuffer the water to use insecticidal soaps and things like neem oil or just plain vegetable oils.

GNS: Do you feel the issue of water quality is being seriously addressed?

Ethan: [Unfortunately,] small growers are not spending enough time making sure their water is of a high-enough quality, nor do they understand [that] it changes [from] month by month and week by week.

The big growers in floriculture and cannabis know [that] their grows live and die by water. In many grows, [after the] cost [of] labor, water is the next biggest expense. If you hand-water a commercial grow, you are not spending the time in the correct place in the grow.

So we don’t spend enough time worrying about water.

GN Member: My dad would say in yiddish “lo-mich ales zain” – “Let’s all of us see!” You need to test this theory for water activity. A local cannabis lab can help you with this.

Ethan: “Oh what a beauty”? Was he talking about girls? My grandfather would say [that while] walking across the Yale campus at the coeds. Oy, vas zain goof or “Oh, what a beautiful body.”
My father would call him an alter cocker — old fart.

@heainjectors is part of the forum. If you [are a] a serious grower, this is the best product on the market for getting anything into water. I once thought about an H E Anderson injector as a gift to my brother for a distillation project. Alcohol [though], nothing remotely illegal. They just do not break. And when they need scheduled maintenance it only takes a hour or two to do 12 heads. We had a four-head injector in the greenhouse and a one-head injector on our main supply line. I could not have been in business without this product.

Would a water softener help with water issues?

GN Member: Fun thread, thanks for posting Ethan. Just a quick note for your Kansas water problem — Do you have a water softener on the line? They essentially replace the calcium with sodium, which is far easier for RO membranes to strip out, so your membranes live much longer.

We do dead-res flood and drain hydro, and since I’m one of the nerds who reads white papers, I found one about chlorine injection in hydroponic tomato farms. The tomato farmers found their best yields at 65 ppm free chlorine, over controls, 35 ppm and 100 ppm tests. Cannabis is remarkably tolerant of chlorine levels in hydro systems, up to 100 ppm causes no adverse effects. We use small chlorine tablets to slowly release 40-60 ppm of chlorine in our aerated reservoirs, which also acidifies the solution.

When used with RO and acidic nutes, it’s common to see pH ranges dip into the low 3’s. We use silica as an effective pH up until late flower, when we switch back to a pH Up so as not to have too much silica in the medium and tissue post harvest.

Ethan: When we ran the operation in Kansas we were forced to inject phosphoric acid into the irrigation lines. This caused us to adjust all of our feeds to compensate for the [additional] phosphate. J R Peter’s produced three custom blends to meet our needs.

I would never [use] sodium to soften the water [because] much of what we grew was sodium-sensitive, plus it [would] just throw all [of our] numbers off. We jokingly priced out reverse osmosis for the greenhouses, but between water storage and RO tanks, we would have spent about as much money [on the RO System] as [we did] on the structures.

We used a four-head Anderson injector in the greenhouse. 1 [was an] acid head, two [were] feed heads, and one head [was] for other uses. We also had an Anderson gas-injection head in the 3-inch water supply room. We didn’t like the chlorine levels in our water supply from the city [so] we added some additional chlorine into our water.

Today, I know we would handle the water issues differently. Every grower needs to spend more time thinking about there water.

Why do you say “from the voices in your head?”

GN Member: Hey @Ethan! Thank you for doing this AMA! I’m going to ask one of your suggested questions – why DO you say “from the voices in [your] head?”

Ethan: It comes from an old Yiddish expression [about] deep, contemplative inner talk. My father said it in Yiddish, Isaac Asimov used the line, as did Einstein. Rabbinic scholars would say this when thinking hard about how to apply laws to modern-day problems.

Why are light producers selling products that people don’t want?

Ethan: When are light producers going to give me lights I want? And not what they want to sell?

I want light producers to do thin-film chromatography on cannabis before I buy any lights. Prove to me that your light can match the absorption spectrum of my plants. I want every dollar in my production [facility] to go to the grow.

GNS: I’ll let @Lighting and @EquipManufacturers take a stab at this question.

GN Member: I’d say because the financial sector doesn’t (currently) properly understand the abnormalities in regard to infrastructure capability/demand, or ‘supply/demand’. Neither do contract manufacturers. They say to [our] industry, “Not yet.” – Well, the time will come, inevitably.

For us personally, we’re not selling anything yet; simply because we are busy with other things, and don’t need money from this company, which provides us with a sense of patience.

GN Member: I feel this for sure. I’m testing out a lot of current lighting tech. While it’s pretty good, I feel like I’m missing something – some level of control in the way my rooms are lit. I’m sure build my own. But in all honesty I just don’t have [the] time. Would rather have the professionals who have the right equipment to get it done…

Question is what are we missing [that] you’d like to see?

Ethan: Great question GN Member,

First don’t waste your time building lights. Lights like @GrowFlux [provide] end-user control of the light spectrum.

I also think we are lighting the wrong part(s) of the plant. We know in cannabis only the top 1/3 of the axial flowering branch is producing 80% of the food at flowering. The older leaves are used as sinks for things the plant does not want. Additionally, the plant is stealing Copper from the older leaves and moving [it] to newer leaves.

I also think we are solarizing our plants. [What I mean is that] the excess light not used in photosynthesis is going to waste and is causing problems in maximizing our output. I want some realignment of chloroplasts in the leaves but not past the compensation point of maximum carbohydrate production.

Why are environmental solutions not designed for cannabis? And why do people buy it?

GN Member: Ethan, why do we see less than ideal solutions for temperature, relative Humidity and air movement in the grow space? Why is the equipment not purpose-built, and why do those growers who buy this equipment think it will work? [As] an example, the air flow over a coil is an engineers desire to produce a certain outcome, not one that produces an ideal air flow for any other function such as air movement in the room.

Ethan: This is a question [straight] out of my greenhouse structure design class in college.
There is [one major] point: Grow rooms are different than greenhouse [when it comes to] light control and temperature control.

Both have calculable Delta-T loads for temperature, in both heating and cooling. Greenhouses from the BIG manufactures have this down tos a science, by the part of the country you live in. Nexus and Stuppy build great greenhouses.

[The issue of] Grow rooms [are a matter of] layout. Growers are not thinking about material handling in the production [room]. This is just a maturation issue.

Grow room operators who get it right are going to have the highest gram per square foot-week output with the most consistent product. But, there is a lot of hard science to professionally grow inside. They are also going to be the producers with the best chance of capturing the high-end value in the market. The grow room operator who figures out the whole vertical market is going put their kids through any Ivy league college they want.

GN Member: Growers value VPD, but they do not focus well on the control of vapor pressure in the grow space, typically controlling it indirectly. Thank for your answer.

Ethan: I don’t necessary think industry specific solutions are the answer. We know how to heat and cool large office buildings. And in the USA we do it very well. For example, Honeywell’s environmental solutions are major greenhouse players in Europe for HVAC controls. They cost pennies on the dollar for industry-specific solutions. [The difference is that] Honeywell uses a different sensor density [in] greenhouses than in the people world. They also use a much higher-quality humidity sensor than we see anywhere. The Missouri Botanical Garden retooled its entire People and Greenhouse spaces using Honeywell as a vendor.

Until equipment manufactures give me something unique, why pay a premium? I remember when the first pH pens came on the market. They were expensive. Then we learned that it was cheaper to just throw them out every quarter and buy a new one. I purchased one of the very first computer-based environmental controls systems, [which cost me] about $20k in capital investment to control 16 points. Today I can do the exact same thing with a Raspberry Pi for under $200 and some guy [who] has written a program open source that will monitor and control 1024 points. Why would I spend $20k for a $1k solution?

The bigger question is why are the environmental control manufactures not giving me what I want?

GN Member: Ethan, Some time when you have time, I would like to discuss why I think the suppliers are not providing what is needed.

Ethan: The biggest thing is that suppliers are not listening to growers. The second thing is growers don’t want white papers. They want hard science when making mission critical decisions. The professionals are hardcore floriculturists. They are trying to figure out fact from fantasy.

What producer issues are not being addressed appropriately?

GN Member: Ethan, many great topics…

Can you tell us, in your opinion, what grower/producer issues are not being addressed as they should be? What needs to be pushed to the front of the line?

Ethan: The serious producers, both big and small, need to take sanitation and post-harvest handling more seriously. If you can’t eat off the floor of your post-harvest room, there is a problem. With products like Oxine wt we have a chance to treat cannabis just like any other horticultural crop from a food handling standpoint. Sanitation [has] always [been] a big issue. Cannabis is just going to be harder.

[We also] have the ability to keep our drip lines clean [with the right products]! I don’t have to have a full-time person cleaning drip emitters. Look at a company like Netafim — they make great products, but there is still a labor [requirement] on the grower side. Oxine would have kept my drip lines clean. We ran 4.5 acres of drip lines all custom-designed and about 80% from Netafim.

We [also] have serious post-harvest problems, which we shouldn’t. We just aren’t leveraging what food science people already know. [For example], how many grows use freeze dryers as part of their harvest operations? It solves lots of the problems we have. Plus, there is a freeze dryer for every size grower — it’s not just for the big guys. I used a commercial freeze dryer for cannabis in the early 1980’s, [and] it gives you a perfect bud. Exactly the way you want it.

We also have people smoking TOBACCO in our operations. I don’t have any problem with tobacco use, it is a [personal] choice. But, TMV in tobacco products is a real threat in growing operations, and we know TMV affect cannabis. Hemp also has a virus that I am surprised that we don’t see in the cannabis we grow [called] Hemp Stunt Virus.

Where do you see the future of the cannabis industry in 5 years?

GNS: Where do you see the future of the cannabis industry in 5 years?

Ethan: Let me put on my fortune-telling hat!

  • The market will have big Wallymart and Home Despot growers and a number of smaller boutique growers.
  • The boutique growers who figure out branding and vertical marketing are going to be filthy-rich.
  • The genetics people who can give us reliable seeds are going to win that segment.
  • Vegetative propagation is only going to be viable for a tiny group of boutique growers.

The biggest question is what hemp production going to do the cannabis market? Hemp is going to be commodity-priced by fiber quality.

Cannabis as a recreational product has some challenges. We don’t have a good language to talk about cultivars on the production side, nor do we have a good language to talk about the consumer side. On the consumer side, we need to define a language that does not mention any fruit flavors or candy flavors. We should [be able to] describe the sweetness of purple kushes as having a pernod-like flavor with a hint of Angostura Bitters

GNS: I think we can agree that the future is bright for cannabis! As much as I love the idea about naming conventions, I suspect we are a long way from such professional nomenclature!

Ethan: We can dictate the nomenclature as an industry and [choose to] talk in those terms. We should take the wine approach to talking about flavors. I don’t have a clue how we talk about the effects. The flavors is a real and present danger to us as an industry and we need to take the lead. I don’t ever want to see a variety called cotton candy!

The future is very bright. And it is a young-enough industry that the growers of today are going to be the big players of the next generation of growers. Our generation has to teach the next generation what it is to be a good grower. But we also need to document our history, the way the old floriculturists did. Read Geo Ball, or Atlas Burpees or Nelson Coon’s books.

Nelson Coon noted in 1925 that most bad mites glow under black light, I have seen this with my own eyes, in both two-spotted mites and russet mites. Predator mites don’t glow though!

What are your thoughts on osmocote?

GN Member: What do you think about Osmocote?

Ethan: I would think your Cal-Mag feed would be a better choice than Osmocote I like Osmocote, but you have to wait. I use it in my house plants.

You [should] have a feed in your inventory that is the ratio of 1:1:1:1, plus traces. N:P:K:Ca plus traces. I would use this in your soiless mix of choice. Feed CLF at 200 PPM up until two weeks before flowering. If they are hungry up [the mix] to 300ppm. Two weeks before flowering, switch to a bloom booster that has a ratio of 1:3:2:1 plus micros. Do this through flower induction. 200 ppm. Then switch back to your regular feed 1:1:1:1 tapped your feed during flower. Finish the last two weeks with clear water. This should give you the highest THC and the best color.

Also warm roots, cool tops, especially post-flower induction. This will give you the best plants.

Low pH is something I am going to have to try. I see advantages and disadvantages.

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About the Author

Hunter Wilson is a community builder with Growers Network. He graduated from the University of Arizona in 2011 with a Masters in Teaching and in 2007 with a Bachelors in Biology.