Cian [00:00:05]:
What's up, Gromies? Welcome to AROYA Office Hours, episode 139, your source for free cannabis cultivation education. I'm your host, Ian, with our director of applied technology, Jason Van Leuven. We're joined today by Liam Spencer, one of our AROYA sales representatives or account executives. And instead of our usual guest interview format, we're going to do a deep dive into some questions that have come in from you guys lately in the community. Liam's not just any sales rep. He's also been on the front lines every day talking to our growers, helping them solve problems, and seeing some of the same cultivation challenges come up over and over again. So we kind of thought, who better to jump on, do an episode with us and talk about the ins and outs of what's happening out there in the field? Liam, want to give yourself a quick intro and tell everyone who you are?

Liam Spencer [00:00:49]:
Hey, guys. Yeah, thanks for having me on here today. Yeah. I come from a commercial cannabis cultivation background and horticulture background. I worked with Pure Leaf for a couple of years and ran a couple small craft cultivations in Denver, Colorado. And then I moved on to being sort of the technical advisor for science led before joining Auroya. So some experience in large scale greenhouse production and small craft indoor production. And I've been involved in the horticultural world probably about 11 years now, starting with doing some hydroponic gardening and community garden work at the University of Central Florida.

Liam Spencer [00:01:33]:
Yeah, that's. That's pretty much my background.

Cian [00:01:41]:
Nice. Well, I know that you've become pretty popular with a lot of our customers out there and you're on the front lines answering a bunch of those support questions as they come in when people have, you know, things pop up and want to get your $0.02 on the matter. So we appreciate you coming on and doing the same with us today. A lot of fun to have new faces on and get to discuss some of these problems from a different perspective. So appreciate the time today and hope it's fun for you.

Jason Van Leuven [00:02:08]:
Yeah.

Cian [00:02:10]:
So here's the rough format for the day.

Jason Van Leuven [00:02:12]:
Right.

Cian [00:02:12]:
We've got some good questions from the community, a handful of ones that are probably bound to pop in on the chat today, but I want to do a deep dive on a couple of questions that we got in that seem like they'll be a lot of fun for us to kind of throw around for a roundtable discussion.

Jason Van Leuven [00:02:28]:
Good thing we've got you and Liam on the call today because it seems like I tend to knock them out as short as I can. So we'll let you guys really dig in.

Cian [00:02:41]:
All right, so we got a couple of topics to go with for the day. The first one that really kind of jumped at me was in regards to EC behavior during late flower and kind of what your drybacks are supposed to look like, what your EC behavior is supposed to look like during that late flower ripening stage. And I know that that can definitely be confusing for some people when we always talk about going back to generative cues in that regard. And I get a lot of questions personally about like, well, what does that mean to go back to generative now that my plants are so big? You guys see similar questions on a regular basis?

Jason Van Leuven [00:03:21]:
Yeah, I'll kick it off, Liam. Yeah, I almost always tell people that ripening is probably one of the hardest of the segments to advise on. It's one of those things where, hey, we're running out of time. And so the choices that we have, the levers to pull as far as our effect on the plant at this point are somewhat limited. Especially when we talk about the root zone and EC and stuff. Obviously, environmental parameters absolutely key to maintaining some dense buds, making sure we don't see foxtailing, try and get as much anthocyanin production as we can out of those last 10 days, two weeks of the cycle. And so it's really critical that obviously we're doing those aspects and we're also trying to prevent any, any mold growth as far as those buds are getting huge. A lot of times our canopies are getting really thick and we're waiting till that last pre harvest default in order to really get things cleaned.

Jason Van Leuven [00:04:23]:
Um, and I think there is more to this question as well, but, you know, in general, yeah, we are trying to run some generative strategies and that can be a serious challenge depending on our substrate size. If we've on the smaller side of the substrate size, then typically we may have to actually push some additional irrigations depending on our substrate type, I guess. I was working with some guys in Rockwell slabs and they're, they're hitting 10% for last 10, 14 days. And they're like, yeah, we're, we're actually just running out of field capacity and stuff here. And obviously when we're in Rockwell, like, yeah, 10%'s not gonna hurt the plant at all because we still have tons of available water. Um, our matric potential is, is not necessarily queuing that plant for any, any damage at that point, but we do have to maintain a high enough water content that we're not going to be, you Know, running out of field capacity before the end of it. So what I should intro there was obviously, when Rockwool, we dry back too much, we start to lose that field capacity, some hydrophobic effects take hold in that substrate. And so really the recommendation there was just, all right, let's, let's, let's not push those huge drybacks until the last, say, seven days.

Jason Van Leuven [00:05:42]:
You see? Yeah, you're going to see some huge dynamics. And we'll get into that part of the question here after Lamb's Peaks.

Liam Spencer [00:05:50]:
Yeah, no, that was a great, great summary, Jason. I think, you know, there's a little bit of confusion in, in ripening that a lot of people have around substrate ec particularly, you know, managing drybacks and EC at the same time, particularly if your input EC is tapering down. A lot of people have different preferences on their input ec. And I think that's one of the bigger drivers on osmotic potential in the root zone with, with ripening. Some people like to flush, some people like to, you know, do different things, but don't necessarily understand ex impact that that might have. You know, one of the core components of ripening is high osmotic potential in the root zone. So if you're driving high ec, that's more of a generative stimulus on the plant. And I think that's something that people kind of get confused where they're trying to taper EC down in the root zone at the end because they want to try to flush it out.

Liam Spencer [00:06:44]:
But that's not necessarily the, the most ideal generative cue on the plant.

Jason Van Leuven [00:06:52]:
And I'm glad you brought up one of my least favorite words, because a lot of what that EC strategy has to do with is whether we are reducing our amounts of nitrogens. Anytime that we're doing some type of strategy, we always need to keep our goal in mind. Right. And so the goal of the old flushing. There you go, I said it is to reduce the amount of carbohydrates and sugars that are accumulated into our flour specifically. And the goal there is, obviously, get a cleaner smoke, always go for that nice white ash that people are shooting for. We can do that a little bit by keeping higher ECs and making sure that the nitrogen supply is limited to the plant. And that's where we see commercial products that are replacing the typical base, um, which is, has that calcium nitrate component and replacing it with a calcium chloride type component.

Jason Van Leuven [00:07:53]:
Um, for all the Athena fanboys out there, that's the fade product, probably one of the, the most known on there. So if we're not tired talking scientific that application wise, that's probably what you're familiar with doing. Um, and when we are not replacing our nitrogen, that's kind of where the, the traditional flush approach came from is all right, well we can get rid of our nitrogen by just not giving the plant any nutrients or very, very low amounts of nutrients. Unfortunately, when we do that, we're limiting its growth potential as well. We're, we're limiting some of the, the micronutrients that are absolutely essential in the full maturity of our ability to produce high THC's, high, high cannabinoid, any of that chemo type, those chemical profile of that flower. So you know, when, anytime that we start talking about ripening it, we have to understand, you know, are we doing a procedure that's reducing the amounts of nitrogen in the substrate and plant. You know, we're not building as many sugars and carbohydrates to that plant cause it doesn't need to storm for growth in the future.

Liam Spencer [00:08:59]:
Yeah. And I think one more thing to sort of add to that is, you know, with the concept of tapering EC down towards the end of flower, a lot of that could definitely be related to playing with different runoff volumes and different quantities of leach it out of the substrate. And you know, if you're not tracking that closely, you could be accidentally driving too much of your EC down because the plant's potentially drinking less towards the end and its demand for water goes down. So you could be, if you're not adjusting your inputs and paying close attention to your runoff, you could see EC tapering downwards just as a result of that.

Jason Van Leuven [00:09:36]:
Great point. Probably one of the biggest challenges that I have when Talking about ripening EC is our ECs typically get to be very dynamic during ripening. Right. Especially if we are tapering nutrient input, which can be a really nice strategy to, to be honest, even if we are getting rid of our, our nitrogen in there, I, I, I do like to taper a little bit towards that end, towards the very end. And when we have such dynamic ECs we get a question like, oh, what should my ECB in ripening? It's like well it could be 3 or 4 and it could be 12 all in the same day. Right. And those dynamics are very typical with the dryback. And that's kind of where this question is going a little bit that we're going to get into the second half.

Jason Van Leuven [00:10:22]:
Just a minute. It's also why time series data is so important when we start to think about turning the Knobs really tweaking what we're doing in our ripening to get the best out of the plant. We're going in there and taking a, you know, a spot measurement on ec. Depending on when we hit that, you know, there could be such a massive range of what those ECs are going to come out as. When we're able to analyze the. Those dynamics, when we're able to see what is that EC doing throughout the day, we get a lot more options as far as making it better and making changes in the variables that we're doing to optimize our flower output.

Liam Spencer [00:11:06]:
Yeah. And I think tying back into what you mentioned earlier about rockwool, I think you've. I've found when I'm looking at data from some of our customers that the, the ones who have lost a bit of their field capacity in the rockwool see much more dynamic ecs in their substrate, particularly towards the end as well. Just because that ratio of water to. To salinity is. Yeah. So dynamic.

Cian [00:11:32]:
I love that breakdown too that you guys both contributed to there of talking about how, you know, the ultimate goal is to reduce nitrogen levels in there and whether or not your strategy to do so is to, you know, reduce your input levels bit by bit towards the last few days there, where you're starting to really draw that through into its. Into its ripening phase, or whether you have been more on that traditional.

Liam Spencer [00:12:09]:
Lush.

Cian [00:12:10]:
Clean water approach that Jason's so fond of, if either direction. Right. What you're doing essentially is trying to draw that nitrogen level in your substrate down a little bit so that you are encouraging that product to finish and to harden and to get the full potential out of what you've planted. And I think that helping people to understand why they're doing what they're doing from the traditional standpoint of the flush concept or from the metered approach of dialing down your nutrient inputs over time is really important because a lot of people that I talk to don't necessarily understand why they're doing what they're doing. It's just what's worked for them over time. So I think that that's really important to communicate and I think it's a really juicy piece of information for people to pay attention to in there.

Liam Spencer [00:13:07]:
One thing I wanted to add is do you guys often see as well on the Teros one data where overnight, when you see your overnight dryback. I find when the EC is pretty low, sometimes you'll see tapering downwards with the dryback sort of in tandem or in parallel with the dryback. So that's sort of something that I've notice fairly infrequently but still present. I think that might be something that some growers are probably asking questions about too.

Jason Van Leuven [00:13:36]:
Yeah, you kind of brought us into the second segment there of this question. I did want to share, do a little screen share. Probably been a while since we've put some actual stuff on the screen here. So when I talked about those dynamics, let's see if we can share screen and if our awesome producer Chris over here can, can get, get me on the screen here. We'll, we'll, we'll show some, some actual data here from one of our partner facilities. And this is the last 1, 2, 3, 4, 5, say five or six days of the cycle. And these guys do a great job. Actually probably a little bit less dynamics than, than I see some places, but here.

Jason Van Leuven [00:14:19]:
Yeah, we can see. Okay. After irrigations they're getting down to that say 3 to 4 EC, which is fantastic. I mean that's, that's a great be in your root zone during ripening sometimes, sure, we could go a little bit, a little bit lower maybe for the last few days, but for a cannabis plant, most of these things are pretty hungry. And so anytime we start getting too low in EC it's going to be starving that plant and, or asking for some amount of deficiencies. And one of the things, this question, I think probably the most important reply to the question that we have here where they're seeing their eclipse drop during drybacks is what are some of the absolute values? Right? Where is our feed EC at? Where is our zone EC at? Because anytime that our plants are eating more nutrients than what is available in the root zone and or what we are supplying, we're going to see that EC drop, right? It's just going to happen. Those plants are eating nutrients faster than we are supplying them. And from my perspective that's really never a good thing at any point.

Jason Van Leuven [00:15:27]:
Probably, probably at the end it's not as bad as any other part of the cycle be because you know, a lot of this plant has, has built up some of the chemicals that it needs to catalyze into the, the final products those, those chemicals, those final chemicals that we're looking for out of the cannabis plant. And obviously it's not going to have a long term impact on the growth productivity of it. But that still being said, if we had an idea of where those absolute values are, if I am actually flushing and let's say my PDC is 0 or 0.5, depending if I'm RO or municipal or well water, for example, Then our substrates down at 2 EC, there's a very good chance that the plant is actually drawing the substrate to almost no nutrient content.

Liam Spencer [00:16:25]:
Yeah, that definitely shifts the osmotic balance to an ionic balance in the substrate. That can be definitely counterintuitive. I've seen, or at least counterproductive. I've seen in cases where you're driving everything out, you're changing the osmotic pressure too, in the cells of the plant. And that's where you can get a lot of risk for mold in the tissue.

Jason Van Leuven [00:16:50]:
Do we want to talk to talk. Do we want to dive into osmotic potential or do we want to keep. Keep rolling here?

Cian [00:16:57]:
I think for the moment we'll keep, keep rolling on this one for a little bit here because I think it's a common enough question we get from people, especially in regards to that drop in ec. As you're watching your plant, you know what would normally be a little bit of a rise throughout the day become a dip for you. A lot of people get really alarmed by that and it is alarming, you know what I mean? Like, you look at that and you're like, oh, my gosh, what's happening here? And one of the first things, and I think you pointed this out, or point, at least pointed to the data point there that I always talk to him about. I'm like, what did you Change your Feed EC2 recently? And more often than not, they've just gone through a big reduction in their feed EC that maybe was a little more drastic than they should have maybe gone right off the bat. And as a result, they're seeing less available nutrients for that plant to be able to use up throughout its photo period. And, well, just like you said, that's going to happen. That decline on the graph of your EC values is the natural result of having not enough nutrients there for your plant when it's hungry enough to blow through what's there.

Jason Van Leuven [00:18:15]:
And then, then you blow through the flower after you cut it. Chris left.

Cian [00:18:29]:
Yeah. This question came in from one of our Instagram followers. Essentially he was saying that, you know, he's saying when he's pushing hard drive backs towards the end of flower, that's exactly what happens. And this customer specifically, I think, was an Aurora Go customer that was noticing this and really wasn't sure what to make of those numbers. And oftentimes that's what we find is if we dig into that a little bit, there's some Changes that have happened in their input EC values or potentially how they've decided to irrigate their plants. And sometimes one of the things that I find is that they're really hung up on this idea of moving back to a generative steering cue and what that means in relationship to their understanding of generative steering in the first couple of weeks versus what we're seeing towards the end of the round and how much they can really press that gas pedal of generative stress, so to speak, in those last couple of weeks.

Jason Van Leuven [00:19:26]:
Man, you guys are getting to me today. Stress and flush and everything. Let's take one step back and talk a little bit about our goals of doing generative type of crop steering towards ripening. Like why, why are we doing this? Right? And sure there, there is going to be some strain dependency and I'll bring up the anecdote of some pineapple that I used to grow and pretty much it seemed like no matter what I did with that stuff, it was foxtailing at the end, right? Like beyond a nice crown that we would, we would think of as a reasonably attractive type of foxtailing, right? We're looking at bud elongation beyond what we want to put in, in a bag or a jar. So that's probably one of the really big reasons, right? Anytime that we do multiple irrigations, you know, every time we're doing irrigation event to that plant, we're bringing fresh oxygen, fresh nutrients, we're giving a cue to the plant to basically bulk out. I mean, that's why we call it vegetative bulking for the middle of the cycle. And in this case, you know, that, that bulking towards the end, a lot of times we're going to see, you know, fresh white slash clear hairs on the plant. We're not going to get that nice uniform amber development across the bud.

Jason Van Leuven [00:20:45]:
And, and it's actual morphology is typically less desirable. Now on certain strains they, they're much less likely to express that type of stuff. If we can't stick with a good generative, let's say we're in six by six Hugos and we're trying a bigger plant and it's like, all right, well we got to kind of stretch things out or do some emergency irrigations to keep this substrate from zeroing out on water content. And then the other thing there is thinking about matching this plant's end of life, its end of science, essence cues. And so if we can aid in its maturity, sometimes we can cut a few days off of the cycle. There's a Lot of plants that, you know, we would typically run it, save, you know, 10 weeks. A lot of times we can get them down in nine weeks if we do a great job with our generative type of steering towards the end of the cycle. So those are really some of the main reasons that.

Jason Van Leuven [00:21:45]:
That we're going with the generative approach during the ripening, say, last one to two weeks, you know, 10 days, 14 days.

Cian [00:21:58]:
Yeah.

Liam Spencer [00:21:58]:
I see so many of my customers getting. Getting lost in that. In that last phase, too, like you had mentioned earlier, Jason. And I think what. A lot of times they're probably looking. Not zoomed out enough and looking too deep into these specific triggers and cues that they think that they're chasing without really understanding the principles that drive what we're trying to accomplish here. So I appreciate that, that insight. That's helpful.

Cian [00:22:32]:
I also appreciate that you wanted to take the time to break that down because I was kind of baiting you there a little bit. I hope you don't mind, Jason.

Jason Van Leuven [00:22:40]:
All right, man, you just got to spell it out for me.

Cian [00:22:42]:
Sometimes I get so many questions to that effect, right. Where people are, like, trying to stress the plant out right now. Right. And I'm like, not necessarily. No, you're definitely trying to transition back into what you would consider a generative style steering strategy. But if you're hitting temporary wilting point as a result of trying to push the gas pedal, so to speak, a little too hard on your plants, you're definitely not going to make that plant perform better in its last couple of weeks. And hope you don't mind me baiting you into explaining the ins and outs of why we're doing what we're doing and going into that generative steering strategy, the ripening stage there. Because I just find it such a confusing thing for so many people.

Cian [00:23:31]:
You know what I mean?

Jason Van Leuven [00:23:32]:
Yeah, absolutely. I mean, maybe we just want to go out there and actually just talk about stress. Right. When we are working in agriculture, horticulture especially, where we have the ability to manipulate that and sometimes play on the edges of. Of stress, there's two main stressor factors. When we look at traditional crops, most of the time we're talking about a drought stress. Right. And a drought stress, it actually has less to do with water content and much more to do with matric potential.

Jason Van Leuven [00:24:08]:
And this is because this is why cannabis is super fun, is a ton of our clients are all hydroponic. We've got cocoa or rockwool, some type of peat mix. Right. And that means that we actually know when those matrix potentials are getting low, we can chart those in specific to water contents. When we're looking at water content for cocoa, for example, we usually start to see some type of stressor events at about 15 to 20% volumetric water content. And that's simply because the properties of those substrates are, they're related to how much they're holding on to that water. Right. And when we're talking about a drought stressor, the plant is applying a vacuum to this substrate.

Jason Van Leuven [00:24:58]:
And when it has to apply too much vacuum, we can start to see temporary wilting point depending on if, if, if the osmotic tooker pressure, you know, the osmotic difference. We'll talk about osmotic in just a minute. But the tugger pressure of those cells is able enough vacuum to the substrate in order to pull the water out. Right. Now if we get to a point where it's actually not able to survive at the amount of water that it's pulling out, so we have a very negative matrix potential because it's pressure. So vacuum would be negative. Then that's when we start to hit a permanent wilting point. You know, a permanent wilting point is going to set in on that plant at different areas of the plant, right? It's going to set in in certain areas and as that plan becomes closer to being completely dead, you know, it'll set into the entire plant where we see that permanent wilting point, temporary wilting point is the fun one.

Jason Van Leuven [00:25:54]:
This is where we can apply some drought stressors, especially in more traditional types of crops. And that can actually aid in changing the plant's hormone balance. It aids us in basically steering the plant physiology. And we love the term crop steering here and in the cannabis industry because a lot of times we didn't necessarily have enough history, enough growing guidelines. There wasn't the transparency on, on, on plant behavior. And a lot of this stuff was just, just happening behind closed doors where the demand for any type of smokable product was so high that we didn't necessarily need to dive into them. Right. Not being said in hydroponics when we're playing with temporary wilting point, you know, it's one of those things where we actually may not have to.

Jason Van Leuven [00:26:48]:
There's another type of. I don't know if I stressor, we'll call it stressor. I wish I could come up with a better word because that's not my favorite. I usually like to talk specifically about, you know, the actual biology that's going on that's causing the change but sure, when we are working with osmotic differential, and, you know, you can hear Liam saying osmotic potential, I like to refer to it to a differential because we're referencing the osmotic pressure in the substrate and the osmotic pressure in the plant itself. Typically, the osmotic pressure in the plant, well, the salt content in the plant is going to be at a higher concentration than in the substrate. And until we get to really high ECs in the substrate, which we typically try to avoid that. But that osmotic differential is we raise our ecs, it decreases. Right.

Jason Van Leuven [00:27:43]:
And so that can affect things like tooker pressure. It does affect a little bit of our water and nutrient uptake as well. And so by manipulating our salt concentration in the substrate, we can basically modulate how that plant responds.

Liam Spencer [00:28:02]:
Yeah, that's. That's good clarity there. I think that that is really useful. I think, you know, you taught me a while back to use the term stimulus on the plant as opposed to stress, because when get to a point of stress, typically we're doing damage to the plant. And there's plenty of data and research out there to support that. Drought stress in cannabis specifically and hydro can actually be counterproductive to yields and quality. But yeah, riding that line is more of what we're kind of targeting, I think, is what you're. You're getting at too.

Jason Van Leuven [00:28:35]:
Good. Good backup.

Cian [00:28:38]:
I'm happy you guys got into that a little bit, because that's another one that just a terminology of stress. Right. I really hope people start to use the idea of stimulus or steering cues rather than the idea that what you're doing is always stressful to the plant. Because, like you guys are saying, stress implies that that plant is going through something that is not necessarily going to be inherently positive to the net outcome that we're working towards. And I think it's good to get to a position where we start to differentiate what we're doing in terminology from stressing the plant, which sometimes maybe we are doing just that. But also looking at, you know, are we stressing it or are we giving it signals? Are we stimulating it to do a specific thing? Are we looking to, you know, elicit a response from the plant? And I think that that sometimes might be a better way to start talking about those subjects than the traditional stress that we hear from people so often.

Jason Van Leuven [00:29:47]:
It kind of reminds me of a really cool research study that I heard about at a conference one time, and these people were actually intentionally inducing pest pressures into cannabis in order to see the response Right. And sure you could say okay, well this is a stressor on the plant or whatever. And really the reason that I'm bringing this up is because it, it's a response from the plant where they actually saw higher THC content concentrations a little bit, a little bit higher chemical output from the plant in defense of the pest pressure that was applied in this case. No recommendations to do this kind of thing out there guys, but just, just these plants can respond to types of environmental factors that, that we get to manipulate in indoor polar, cultural or mixed light horticulture.

Liam Spencer [00:30:45]:
Yeah, I think without even using pests, you can probably induce the same thing through some organic compounds like chitosan or some of these more typical, you know, organic additives that people use to stimulate the ISR and SAR pathways in the plant. Without know that's, that's sort of something we, we could learn from the extremes of like what you're talking about where we're heavier pest pressure. What is the driving mechanism in the plant producing more compounds that way and can we do that while also driving higher plant health?

Cian [00:31:18]:
That's a great addition, Liam. That could almost be a whole separate discussion unto itself. Before we get too deep into that one though, I do have another direction. I want to take our conversation for the day because I think we could probably get lost pret quick there. So the other big topic I wanted to cover today is in response to a couple of different discussions that Liam and I have had lately that have to do with commercial irrigation uniformity and troubleshooting problems that occur at large scale. When you don't see uniformity in your VWC readings or in your drybacks potentially what that might mean when you're looking around your facility and how to identify some of these issues. So the question I got in here from our cultivator is I'm currently growing on a 32 foot bench with about 68 to 75 plants per bench using Net FM 1 gallon per hour emitters. I'm seeing the fronts and backs of the tables are always running 15 to 20% higher than in the middle of the tables.

Cian [00:32:28]:
Our emitter tests look good and consistent, but it's not translating. Once the plants are in benches. You know, we see this quite a bit. Liam, I know you and I, like I said, I've had some conversations recently to this effect. Wanted to throw this out to you guys and have you guys each kind of break down what you think might be going on here for this person. One thing to note in here, he does at some point say moisture Content. I'm fairly certain he's referring to vwc, so. So throw that out if you're looking at that.

Cian [00:33:00]:
Jason, let's kick it off with you, man. What do you think?

Jason Van Leuven [00:33:03]:
Yeah, I'm just going to hit on the two things that I see most. This is separate of the question. This is just kind of based on talking about your intro there on the question plant uniformity in scaled agriculture. Well, when we are using sensor to analyze it, the two issues that I run into still fairly commonly is difficulty with sensor installation. So if we're using round hard pots and we don't get that sensor flush with the media, if we're not doing a great job getting that sensor in level and completely flush with the substrate at the height that's recommended for those, we're going to see variations in the readings and that's a false representation of the actual variation that's going on there. So we need to make sure that the tools that we're using to evaluate uniformity are truthful and are giving us a representative sample of that system. And this is really where looking at sensor densities. I know I did a video about that a couple years ago.

Jason Van Leuven [00:34:11]:
When we're looking at populations and how to analyze that and get a good average and what to do there. And then the other difficulty that we can have is. So it's sensor installation and then. Oh, I forgot my other one. It'll come back to me by the end of the question here. But to answer your question, part of it is a lot of times we're looking at canopy uniformity. So center of benches, we're getting less exposure to light. Sometimes we got less airflow in there and so we're seeing less evaporation, less transpiration, less radiant, less radiation on, on those plants in the middle.

Liam Spencer [00:35:05]:
Yeah. I think one clarification I would like to have from this question is are we talking 15 to 20% less dryback or are we talking overall 15 to 20% less field capacity? I guess I was a little confused. You know, he's saying I'm seeing 15 to 20% higher moisture content on the edges than in the middles. And meaning if you know, under the assumption that that means that he's drying back harder in the middle, that could be a function of what kind of lights is he using? Is he using HPS, is using High Bay LEDs? Are we using, you know, grid lights? Are we seeing higher intensity, maybe higher transpiration in the middle? Or I guess that's something that I'm trying to understand is which direction are we going with the water content here?

Jason Van Leuven [00:35:50]:
I'm glad you said that.

Cian [00:35:51]:
Observation.

Jason Van Leuven [00:35:52]:
Yeah, I'm glad you said that. I was thinking of it backwards. Most everyone has the opposite where the middle is higher moisture content. So I'm super glad that you said that. Which makes me actually think of something else and that would be possibly is the microclimate in the center of the canopy.

Cian [00:36:09]:
Wonder about indoor canopy ventilation.

Jason Van Leuven [00:36:13]:
Yeah. Is our VPD more ideal towards the middle? So we're seeing those higher transpiration rates.

Cian [00:36:18]:
Yeah, yeah, that's kind of what I was wondering.

Liam Spencer [00:36:21]:
I was going to say that climate is going to be the huge factor one way or another and planting density and volume of substrate in that area. Because if you got higher leaf density and higher, you know, biomass density in the middle, that definitely will impact it, you know, in, in the converse way of saying, hey, we may have higher biomass density, we may have higher drinking rates in there, or if we're having less light penetration, we may see less water consumption. So just really clarifying which direction that we're trying to. It's probably most likely environmentally related, not pressure or dripper related. But again, that's predicated on which direction we're going with the water content.

Jason Van Leuven [00:37:06]:
Yeah. And you nailed it. There is if we are able to group things by some specific variable. In this case, he's mentioned that the grouping is by area. Typically emitters are going to clog at some amount across it if we have a good irrigation setup. That being said, occasionally, depending on how we have that set up. So if we, for example, have end runs, you know, a lot of times are we're going to see less pressure down here at the end of these runs. Right, sorry.

Jason Van Leuven [00:37:44]:
The black is the bench, the blue is our irrigation supply for those drippers. Right. And so anytime that we're doing that type of stuff, we always want to do a complete circuit for that irrigation that's going to just basically help all of that stuff even out. Right. And a lot of times it's really good to have a, you know, a flush down here at the end as well. That being said, obviously, emitters are very easy to check, you know, as he talked about. So that's, that's, I think most of what we've got to help him here. He's back.

Jason Van Leuven [00:38:21]:
He's backwards. Most people see higher water content in the, in the middle.

Liam Spencer [00:38:27]:
Yeah. I guess if you were seeing lower water content in the middle, it would just, just be, yeah, are we having more ideal transpiration happening or, you know, the pressure testing Saying, hey, yeah, we pressure tested. We think that the emitter is. Are not the issue. The protocols for testing those emitters too, you know, trying to understand, hey, how many samples are we collecting off of the emitters? You know, can we completely rule out clogging as a. As a potential factor here? Because it's less likely that you'll have clogging in the middle of the line, as kind of you said, Jason, as opposed to towards the end of the line, unless you have, you know, some confounding factors there. So, yeah, this is a little bit of a. Of a tricky one to look at from sort of the other angle, because I agree with you.

Liam Spencer [00:39:12]:
I think most of the time we would see lower transpiration in the middle.

Jason Van Leuven [00:39:19]:
You know, other things to consider here. We've really given this guy all the options in the book to go investigate locations of H Vac equipment. Right. Are we seeing the AC outputs all towards the edges or something? Are there dehum towards the middle, heat output towards the middle, that type of stuff? How much airflow do we have really? So that H vac dynamics are very important as far as where we're running. And as Liam mentioned, are we looking at, you know, 15 to 20% across the board usually if we see an offset like that, let's say give me just a minute to draw some stuff here. So let's say 65 and 45 and then. Sorry, guys, I am not that fast.

Liam Spencer [00:40:21]:
Yeah, and one thing real quick is fans. I think we underestimate the impact of horizontal airflow versus oscillating fans and their impact in a canopy just because of the sheer wind pressure. I think this was something that was addressed in a previous episode with. With Anders. But just talking about, like, the oscillating fans are really pushing most of that air on the outside. So that would make sense where you might see more transpiration, either more or less, depending on the velocity of that air. At the edge of that canopy too.

Cian [00:40:53]:
I was kind of thinking too, I've seen several places over the years, not necessarily bigger commercial facilities as often, but every once in a while that have used those high velocity room dryer fans to move a lot of air under their canopy that would otherwise be not quite as efficiently mixing into the air column.

Jason Van Leuven [00:41:16]:
Right.

Cian [00:41:17]:
And I kind of wonder about that, like maybe this person has some directional airflow moving through the center. Think something like that. That might be encouraging. Extra transpiration like that.

Jason Van Leuven [00:41:34]:
All right, now we got some representation. I actually just started the question with some graphics because it always helps us think and helps other people see what we're thinking. So as Liam had mentioned, or you know, we're talking about the graph on the left or the graph on the right. Right, right. Where field capacity on this one, for example, we're seeing it much, much lower. Anytime that we are working with similar substrate in a room, we should typically see these field capacities be pretty much spot on when we start the cycle. It's cool. Those that some of that sample data I was showing you earlier, they were plus or minus like 1 1/2% on the consistency of their field capacity.

Jason Van Leuven [00:42:19]:
When they started their one of those runs in the room, they were running a cocoa product there. One of my favorites, kayakura. And I was amazed like most of the time when I. When I see water contents, I'm pretty happy if I'm, you know, plus or minus like 5% across a, you know, thousand square foot room, say 10 sensors. Well, that's pretty reasonable, right? We can make good decisions off an average for that or even group decisions. So if we are looking at this one, sorry, I was off screen. It was probably more likely a system issue, right. Did we do a shitty job hydrating our substrate? Did we have a hard time installing the sensors if we were middle of the row rather than middle of the column, like he's talking here, maybe it's just harder to do a good job installing the sensors because we got to reach in there, there's less visibility, you know, that type of stuff.

Jason Van Leuven [00:43:20]:
And, and so if it's this case, definitely want to dive in and, and take a look at, at that type of stuff. If we are this case over here, this is definitely plant response, right? So this is actually a different amount of transpiration. So when we're seeing drybacks, they're very rough estimate graphs. Today, y' all, these are different amounts of drybacks, right. So this a lot of times can indicate a plant health. You know, this is plant response, right. Our red plants simply not consuming nearly as much water and or we're seeing significantly less evaporation from this plant up here as well. So if we do, you know, nail it down saying, hey, this one's transpiring quite a bit less, then we got to, then we really got to dive into the well cloning consistency is one of the first things I always like to look into in uniformity.

Jason Van Leuven [00:44:14]:
How well is our process helped our plants stay the same up to that point and then just general plant health things.

Liam Spencer [00:44:24]:
Yeah, I think one of the things about the graph on the left is that's probably More likely to happen or sorry on your. You're right, that's probably more than likely a rockwool scenario. If you're delivering too large of shots or too frequent of events, you can lose field capacity more easily. If you're having that's a compounding effect of having inconsistent transpiration too is maybe your substrate doesn't have the same dynamics within it because you're just not allowing the plant to dry back enough or maybe too much. So either way you can Rockwool is very sensitive in field capacity on intervals and shot sizes once you drive back to a certain point.

Cian [00:45:06]:
Glad you brought that up because that's definitely one of the scenarios that I see that graph Jason had on us right there. The most frequently is when people have done some combination of issue with either their shot sizes, the intervals in between the shots or the total volume applied to their rockwool over the period of time they were trying to use as their irrigation window. And glad you brought that up because that's definitely one of the more frequent calls I've received recently on you know, why am I seeing so much variability across this facility, room to room, tray to tray within the room. And a lot of times those rockwool clients that have that type of variability may have damaged their Rockwool and dried back be below that floor. And as a result they're now seeing a different field cap and a different delta on their dry back than what they had going previously. And so I think it's worth pointing out that that can definitely be substrate dependent as well.

Liam Spencer [00:46:08]:
Yeah, you and I just did troubleshoot an exact case like that in Michigan recently where they're running slabs and they were seeing a range of about 40 to 80, 75 to 80% in field capacity in the room. And they were just very confused as to is it a sensor issue, is it a substrate? They didn't really understand these concepts. So I think that's this is really pertinent because we just solved this problem like last week.

Jason Van Leuven [00:46:32]:
If you are using data driven horticulture principles, getting your field capacity up, getting your substrate saturated appropriately is probably one of the most important things that you can do to set yourself up for a successful flower. One of the most important things during flower that you can do, if you have inconsistencies there and you don't get them sorted out immediately, you're just going to be chasing your tail. The data is going to start to steer you in the wrong direction. As far as some of this stuff goes, a lot of times your uniformity is going to get even worse from there. So when you think about, all right, if we had really good cloning consistency, well, let's keep up our hard work and do a really good job with saturating our substrate. There's a lot of great sops out there published straight from companies like Roto Dan on how to get your slab substrate or your slabs saturated. Read them, follow them, enforce them, and then look at your graphs and verify that that stuff's been been followed.

Cian [00:47:40]:
Brings up a great point. I really like to encourage people, you know, watch that data and trust the data, because this is another one of those scenarios where whenever I see big inconsistencies, it's usually because the sensors are giving you a red flag to pay attention to. And this is one of those scenarios where rather than look at the sensor and say, this value is erroneous, I'm going to keep doing what I'm doing. It must be wrong. I always like to take opportunities, especially with my own sensors, and say, if it's telling me something I have done something wrong, that has gotten me where I am. Because I've almost never ran into a scenario where the sensor has been incorrect. I actually can't think of a sensor that has been entirely incorrect yet unless it was broken. So that's one of those scenarios where I'm like, hey, this is a chance to go in, take a look at what's happening and try to correct some sort of inconsistency that's happening that is in your SOPs or how you're handling this irrigation strategy within your system.

Jason Van Leuven [00:48:47]:
One of the really cool things about cannabis crops is when we are doing cloning and we do a good job of these processes, they are typically very uniform, right? Biologically speaking, genetically speaking, these plants are destined to grow about as alike as almost anything in production of any biological production that people work on. And so if we can keep up a good job on that, it actually gives us more time as a gardener to and more ability. Anything that is wrong stands out, right? I was working with a new client yesterday that they hadn't quite gotten to a point where their irrigations were consistent day to day. And I was like, I just kept asking questions, well, what's going on with this irrigation? What's going on with this irrigation? And sure, they all had great answers for the situation they were in. But that being said, when we can establish uniformity, things that are going wrong, things that need maintenance, need to be addressed, corrected, they start to stick out like a sore thumb, right? And that happens Both with uniformity and with consistency.

Liam Spencer [00:50:04]:
Yeah, I think to caveat that, or at least sort of on the flip side of that, having very little uniformity within your canopy makes data driven and precision decision making very difficult. If you don't have representative plants in your group and your deltas are pretty substantial, then you're not able to really utilize our data accurately to make those decisions. And that makes it very challenging because then that compounds over the flower cycle, certain plants drink less than others, certain other plants may drink more than the average. And when your variance increases so much much, your ability to manage the entire ship as a whole becomes much more limited.

Cian [00:50:46]:
I always like to tell people some when I get on the phone with them that the sensors are only as accurate as you are consistent with them. And if you do not pay attention to what you are doing with them to take measurements, the measurements that you take will not mean as much to you. And so that's kind of one of the big things I try to harp on right at the beginning when I get people onboarded into taking a lot of these measurements and paying attention to sensor driven decision making. And the institute data feeds that we provide them is like this is an opportunity for you to really dig into why you're doing what you're doing and how to prevent you from making big mistakes that could potentially cost you if you are not looking at this and paying attention.

Jason Van Leuven [00:51:41]:
Yeah. And we don't have time to jump in the slides today, but great video that talked a lot about this stuff here. I'm pushing myself. You judge the video. I thought I did a good job on talking about crop uniformity and sensor density, basically bringing up some of this stuff. As far as any of those things that we talked about with some graphics that might help help kind of connect with how other people see these things. So we've got pictures of multiple cultivar crops, we got pictures of heat gradients in rooms, dripper clogged drippers, all that type of stuff. So go check out this video.

Jason Van Leuven [00:52:23]:
It's been out there for it looks like three years now. Good way to think about this stuff as well as population success. Go.

Liam Spencer [00:52:33]:
Yeah. And I think the data also reveals a lot of the inconsistencies within the crop and canopy as well. So having the data allows you to understand how big of a variance you might have within your system as well.

Cian [00:52:49]:
Another great point. It's a good way to be able to gauge, you know, is this affecting just a handful of planets or areas in my facility, or is this a scale problem that I'm seeing across the board in every room. And, you know, if so, so what am I doing? What's producing this?

Jason Van Leuven [00:53:08]:
And it doesn't come just down to sensor data as well. If you're doing a good job looking at your metric state and you have some of those compliance that track and trace data, or if you're just doing a good job internally with some of this process management type stuff, we can look at. Well, maybe, maybe Jason's not a very good cloner and those plants over there were ones that he cut. Let's get him doing something else or find him a new job, that type of stuff. Is there something related to a specific mom that these plants came from? The better that we can identify that variable. In this case, he was talking about the middle of the bench. Probably actually a spatial variable in this chance, but a lot of times that comes down to traceable process actions that happened earlier on as well in the plant's life.

Cian [00:54:09]:
Well, I'd love to go a little further into some of those traceable process actions because I know that, you know, paying attention to a few of those details, so to speak, is how a lot of those big mistakes get solved early on. You know, finding your way into consistent and really stable practices that you can repeat over and over again that are producing quality, consistent results can be a big battle that people fight when they're not paying attention to some of those early aspects that you are talking about, like, you know, your cloning consistency in your early plant life.

Jason Van Leuven [00:54:47]:
And.

Cian [00:54:49]:
While I would love to jump further into that, I think that'll get us into another half hour discussion, which maybe we should save for our next time on there. But I want to just first, before we start closing out, thank Liam for coming on today. This is a blast, man. Hope you come join us more often.

Liam Spencer [00:55:05]:
Yeah, no, thanks. Thanks for having me. I definitely appreciate it. Hopefully I added some. Some value to the discussion for everybody.

Cian [00:55:13]:
Absolutely. What do you think, Jason?

Jason Van Leuven [00:55:15]:
I so stoked to have Liam on. He's. He's a good dude. Like, he fully. You wouldn't think he was a salesperson when you meet and hang out with him and stuff, but. But he's a good one. So our lucky day on here.

Cian [00:55:27]:
Might want to take you out for a date, Liam.

Liam Spencer [00:55:31]:
Anytime, Jason.

Cian [00:55:34]:
Oh, man. All right, well, want to thank everyone for jumping on today. That's episode 139 of Office Hours. Thank you, Liam, for jumping in, bringing us your perspective on everything today, both agronomically and hope it helps encourage people to understand that our Salespeople, you know, don't just talk the talk. They walk the walk. So. So give Liam a call, set up a demo. That way you guys can see what we're about firsthand.

Cian [00:56:02]:
Keep those questions coming. The deep dive format is something we might do a little bit more of. I'm having a lot of fun doing it. I hope you guys have been enjoying it. Jason, Liam, and I know we've gotten some good comments from people taking a few of the customer questions a little bit slower and diving into them a little bit more deeply. So we can hopefully give you guys some good value. If you guys have some more questions for us, please shoot them over for us at either Salesaroya IO or you can slide into our DMS on Instagram, Facebook, or LinkedIn. If you're loving the podcast, please leave us a review, subscribe, or give us a couple comments on YouTube.

Cian [00:56:35]:
Tell us what's up. We'll see you guys on the next episode of Office Hours live on episode 140. Thanks so much for stopping in.