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Seth Baumgartner and Jason Van Leuven open the mics for your crop steering and cultivation questions.
Kaisha [00:00:05]:
What's up, gromies? Welcome to AROYA Office Hours, your source for free cannabis cultivation education. I'm your moderator, Kaisha. We are on episode 104. Shout out to our live viewers on the hangout, YouTube and on Instagram, to everyone tapping in on Spotify, Apple Music, YouTube, or wherever you listen to podcasts. Thank you so much for your support. And if you like the pod, drop us a review. We appreciate your feedback. Jason is in the house solo today.
Kaisha [00:00:31]:
Jason, how you doing?
Jason [00:00:31]:
Howling I'm doing great. How are you?
Kaisha [00:00:34]:
I'm good. Good to see you.
Jason [00:00:35]:
Good to see you.
Kaisha [00:00:36]:
You ready to get this party started?
Jason [00:00:37]:
Sure, Amy.
Kaisha [00:00:38]:
All right, we got this question from Terp surfers a few weeks ago. Wanted to start with this one. He wanted to get your thoughts on lowering EC, save 0.5 ec every week starting in week seven. What do you think?
Jason [00:00:52]:
Yeah, you know, I think it's good. So here's. I like to go with two kinds of routes here. And during that ripening period, last two weeks, it sounds like for most strains here, maybe three weeks if you got a real long running strain. Um, yeah, dropping .5 UC is kind of what I recommend. Um, you know, and what really what's going on here is, uh, some nutrient manufacturers. Obviously, you can start supplementing and decreasing the amount of nitrogen that's in your feed. Um, if you are doing that, I don't mind keeping my feet a little bit higher.
Jason [00:01:23]:
So what I'm shooting for, usually towards. Towards the end of flour, if I am, uh, reducing the amount of nitrogen in my feed, is I'll usually go three quarter strength to, um, to full strength, um, all the way to the end. Now, if I'm not reducing, uh, the nitrogen in my feed, then a lot of times I'll drop all the way down to about half strength to. To be there, um, at the end of the cycle. And. And really, you know, one of my favorite things there is, and I like about this question, is the fact that he's talking about dropping it incrementally. And the goal there is really not to make a huge difference, a huge change in the osmotic differential between the red zone and the plant. And that's really key here, is let's make kind of a gradual transition.
Jason [00:02:08]:
So let's have a target finishing EC and then work there through that last two, three weeks of the cycle. We'll call that ripening. Do some generative steering there. So that 0.5 EC, that's probably just almost exactly what. What I recommend.
Kaisha [00:02:28]:
Wonderful. Thank you for the answer. Terp surfers, we appreciate your question and thanks for patience, your patience while we take a little time to get to it. So many good questions coming in. We got this one on YouTube. Someone posted our input. EC is 2.9 to 3.3 and ph is 5.5 to 6.0 depending on the week of flower. Veg EC is 3.0 and ph of 5.5 and plants are hand watered during veg.
Kaisha [00:02:55]:
Flower team is seeing a steep increase in ph values during stretch up to 6.8 to 7.4. During bulking, it starts to back down to 5.5 to 6.0 and then drops to as low as 4.9 by the harvest date. We have two grow leak sensors per tray in all rooms. So we are doing a pretty good job of monitoring drybacks and also tracking runoff volumes. Ph, Ec, any help would be greatly appreciated.
Jason [00:03:23]:
Yeah, did he specify feed EC for flower?
Kaisha [00:03:27]:
Let me see here. So we've got input EC, veg, Ec is 3.0, ph of 5.5 and plants are hand watered during veg. Flower team. No, it doesn't specify.
Jason [00:03:43]:
No worries. I guess we'll start off with the info. I know. Yeah. So ECF 30 in veg is probably okay. And water and veg. Yeah, not, not the best thing, not the easiest thing to do, but still going to be okay. Sounds like your input phs are about right.
Jason [00:04:01]:
Um, you know, for rockwool, definitely hitting that. 5556 is, is usually just about perfect. If we're in coco, typically like to be a little bit closer to five eight, maybe even five nine towards the end of the cycle. So the first thing that I would check here is try and get an idea of what your, you know, your feed Ec is, um, throughout the flower cycle. Right. Are, are we just running out of specific nutrients and solution? And we talked a little bit about that, um, uh, two weeks ago with uh, cations, anions and, and why ph can fluctuate in, in the substrate. So if, you know, if those sensors that you have, have um, the EC level that you feel like you can trust, then start to analyze it. Um, are, are we looking at an eclipse consistently drop after we've irrigated in flower? And so you know what we're talking about.
Jason [00:04:53]:
I guess let's get a chart out. We're going to get rocking and rolling. It's pretty early. So if we, and this is going to be EC in the substrate. And so I'll draw it first if this EC, let's go like this. So this is for EC if it rises when we irrigate and then it continues to drop. Usually that means that our plants are eating more nutrition than we're supplying them. And that's kind of a super easy identifier if you're having an issue with your ph staying stabilized.
Jason [00:05:44]:
Really what's going on here is we're just getting imbalanced with anions and cations by the time that we irrigate the next day. And that'll definitely give you a representation of low ph or high ph. And what's going on there is just as the plants nutrient demands change throughout its life cycle, you're going to, you're going to see that imbalance shift one way or the other. If this is the situation that you're in, pretty easy fix. We're just going to try and up our nutrients, get a little bit more, get a little bit more nutrients in there, right. If this isn't your issue, then you kind of have to dig in and start thinking about, all right, am I, we're getting enough runoff to, to rebalance some of the ph that's in the substrate to also rebalance some of the nutrient imbalance in there. And then also, you know, the next step would be if none of those are applicable, then get, get a leaf tissue analysis and take a couple of those throughout the cycle. And you may even get a few of them depending on different strain demands.
Jason [00:06:46]:
If you're seeing this across all strains or if you've only seen it one strain, then they get those turned in and see what the results look like. They should give you an idea of what specific nutrients in your mix are running low. And that also explains some of those ph swings. So that's kind of the process that I would take in order to rectify what you're running into.
Kaisha [00:07:09]:
Those are some great points that you brought up. Jason, what do you think people have? We've been getting a lot of questions about ph, especially recently, like why is this such a difficult aspect to manage, do you think?
Jason [00:07:25]:
Well, I guess one of the reasons that it's difficult is because it's extremely critical as far as plant growth goes. And, you know, if we don't have, have a stabilized, um, ph, if we don't have our ph in the substrate, in the specific ranges that the plants need for that substrate, we're, we're going to run into issues as far as nutrient solubility. A plants just never going to, it's never going to grow optimized. And so I think maybe it's difficult because one, we don't have a really good idea of. I guess for me, it's like, all right, if we're tasting something that's ph is low, sometimes it's sour. If we think about phs that are high, the plants not seeing it like that, it's affecting the metabolism of the plant via that nutrient uptake. And certain nutrients are soluble at different phs than the solubility of other nutrients at different phs. And so when we choose what ph is right, we're looking at the solubility charts and saying, all right, how do we compromise and get the most balanced uptake? And it's great to hear that this person is specifically doing a good job tracking it.
Jason [00:08:43]:
And they know when they're running into challenges and they know when it's going high. When it's going low. Yeah. You know, it's chemistry. Maybe that's one of the challenges. It's a little bit harder to grasp simply because I guess what. How I was trying to answer the question is it's not as tangible as some of. Some of the other considerations that we encounter when we're growing.
Kaisha [00:09:07]:
Yeah, I hear that. Amazing. Thank you so much for your insights on that. And just a tip to the person who posted this question. A couple episodes, we did a nice little deep dive into ph, and then we also have a blog post about. That's on our education guides right now. So we got some resources for you, but good luck. Keep us posted.
Kaisha [00:09:23]:
Let us know if you have any other questions. All right, we're going to keep it moving. We got a couple questions about silica. So I don't think we've talked about that too much on the show. So let me start with this first one. This was dropped by a Jedi a few weeks ago. They want to know what's the deal with adding silica. Cannot get it to fall out.
Kaisha [00:09:41]:
What do people use silica for? We can start there.
Jason [00:09:44]:
Can't get it to fall out. Or it is always falling out.
Kaisha [00:09:46]:
They put cannot get it to fall. Oh. Cannot get it to not fall out. Thank you for that clarification.
Jason [00:09:53]:
Cool. Yeah. So, you know, it sounds like, you know, it's not getting into the. Not getting mixed into the nutrients very well. I, you know, I think most manufacturers are suggesting it's one of the first additives. Yeah, I was just referencing some of the front row documentation there. And so some of the steps that, you know, I would take is one follow the manufacturer's recommendation of when it's getting injected. Because what it could be do is if we don't get it injected and mixed at a low enough, you know, a low enough dilution then, or high enough dilution, depending on which one you're talking about.
Jason [00:10:30]:
But if it's not diluted enough, then it can precipitate with other chemicals that we're injecting in that nutrient line. And so, you know, if we're direct injecting, you know, making sure that one, our injection rates are good, our stock concentrates are good, and that we have sufficient mixing. Um, so usually we always want to have a mixing chamber between each injection, uh, in that direct injection line. And if we're going on a batch tank, then obviously you're making sure that that ingredient has dissolved fully into the batch tank before we add the next ingredient that we're building into solution. So, you know, I'd also recommend going with, you know, some of the more common silica additives in the industry. Yeah, some of are kind of expensive, but, you know, the goal here is to build a little bit healthier plant cell walls. And that can help with reducing any mold, mildews and pests, because those are always, always trying to find the weak link to, to start their growth sites in or eat, depending on what we're dealing with.
Kaisha [00:11:39]:
Oh, okay. So the second question came from market buds and they were asking, what are some good foliar options for veg and flour, silica, Athena stack and similar products? How do we find what our plants need?
Jason [00:11:55]:
Yeah, you know, great question. Silica can be used as a foyer, or it can be, you know, directly fed into, into the nutrient line or batch tank. Both of those are options. You can do both of them. It kind of comes just down to how much time do we have to apply to this? Right, and we add it into the nutrient lines can be a little bit quicker and effective way if we're applying it directly to the plant, it's going to be absorbed through the stomates in these plants and, and might be up, taken a little bit quicker into the plant. Um, so those are both options. Good options. Um, you know, a lot of times I just don't end up getting the opportunity to do as many foliar sprays as might be completely optimal.
Jason [00:12:39]:
So it's really about a risk cost cost analysis. Is it effective enough if we just add it to, to the feed line rather than doing full years?
Kaisha [00:12:51]:
Fantastic. All right, rocket buzz, thank you for asking that question. All right, y'all, we are on live. We are live everywhere. So if you have any questions, be sure to drop them in the chat. We'll do our best to get to them. We got this question in from Zach. They wrote, is there any research shown that there's a use for far red and veg? They're on my think grow model versus.
Kaisha [00:13:12]:
But was curious. I've been told to run them the last 15 minutes to help plants go to sleep. Any thoughts?
Jason [00:13:20]:
Yeah, great question. So, I mean, I always love talking about light. Seems like every day there's more and more research that's being dedicated to specifically photomorphogenesis. So that's talking about the plant's response through its life cycle to light. And that can also be a study of this question itself. Um, I, you know, as far as, uh, making the plant go to sleep, I don't necessarily know that that's, um, the specific response that the plant has. But. But in general, basically what we're looking at is when.
Jason [00:13:58]:
And maybe I should bring this up on my computer. Um, I can try and draw it. You all tell me if my drawings suck. Um, but basically.
Kaisha [00:14:08]:
I love your drawings, Jason.
Jason [00:14:10]:
We have. Let's go. You know, around 400, around 700. So we have chlorophyll a and chlorophyll b are kind of the main two components in the leaf that are responding to light for doing photosynthesis. We also have some secondary metabolites that are enabled when we're hitting specific spectrums. So that's our cryptochromes, phytochromes, and those are a little bit more complicated. That's typically what can be activated when we do start working with ultraviolet or infrared is manipulating how much activity we have in those secondary metabolites. There's been a little bit of research done on this for traditional, aggressive, and, you know, a lot of times they talk about, all right, we want a little bit more blue spectrum early on.
Jason [00:15:09]:
That's going to induce some of the more vegetative growth that we're looking for. Trying to get the stock stems and the plant size up and then, you know, pushing it a little bit higher in the wavelength spectrum towards the end of the cycle, simply because it's going to be helping increase terpene profiles, thc levels, by activating those, the secondary metabolites that we talked about. So let's see. Actually, I'm just going to bring it up because I don't know that I can draw enough detail to convey what the best message is here. So we need Seth here to fill it in while I'm looking stuff up. Sorry for all the white noise, everybody.
Kaisha [00:15:54]:
Yes, sorry, y'all. I'm also, we're monitoring the chat, too. This is a pretty well oiled machine we got going on here, but yeah. Jason, thank you so much for looking up a visual. We always love that.
Jason [00:16:08]:
This is not my graph. It's just something that I've grabbed from the Internet. But yeah, this is basically the absorption curves for specific elements or specific biological functional parts of the leaf here. So here's chlorophyll a absorption, and we can see it's got basically two peaks. One here around the 420, then also up here towards, you know, six, 7680. And when we, you know, when we think about it like, this is kind of the reason that plants are green is because, you know, the chlorophyll is absorbing quite a bit of blues and reds, a little bit of yellows as well here. And it's mostly reflecting, uh, light in this, you know, 550 to say, 610, 620 range. And so that's.
Jason [00:17:04]:
That's why we see plants as greens, because they're reflecting that. And so it kind of comes down to, all right, when we start playing with the ratios here of light between 400, 500 up towards 700, we start to impact how these different cells are being activated. Right. And so if we see, all right, when we're pushing weighted down towards, you know, 400, we're hitting some more chlorophyll a. That's the one that's probably more responsible for vegetative type of growth. Right. And so when we're working with something like an HPS light, a lot of times we're going to, you know, we're seeing that as yellow. So we're pretty high here in the 600 to 650 range, and that's going to be activating chlorophyll B.
Jason [00:17:48]:
Right. And so this is going to be kind of the main reason that plants are. They're physiologically responding to different wavelengths and why we have different strategies for different lights. This is why lighting companies are starting to allow you to play with those spectrums, is to modulate the plants morphology based on how it's responding to this. I am getting a little bit off the question, mostly because I don't know that red light is going to be putting the plants to sleep. Not something that I've necessarily looked into. But what we do know is that when we start manipulating these wavelengths, we can change the plant morphology and actually the plants chemology. So when we're thinking about that terpene profile and stuff, we can start to play with these and get a little bit higher by enabling wavelengths that do activate things like cryptochromes and phytochromes.
Jason [00:18:47]:
So let's pull up a chart that talks about wavelengths for phytochromes. So this is kind of fun. It's, you know, these are those, those other, those other cells in the plant that can be, or other parts of the cells that can be impacting the plant's growth here. And so we're looking at a few different phytochromes, the absorption curves for those, and then the cryptochromes as well. And we can see here, this is where some of those ultraviolet lights can start to play impact in how this plant is getting built up. And then also if we look at this phytochrome, far red, the PFR, this darker red line, we can see even past 700. There's some responses to it. You know, this is, this is the basis of why everyone is starting to play with wavelength, is because we can impact how the plant, how the plant is responding.
Jason [00:19:52]:
Um, and back to the question. If it works, then great, um, let us know. I, I don't necessarily have the scientific explanation to, um, whether they are or not feel like they're going to sleep. Um. Right. If we define whether a plant is sleeping or awake, we would probably be looking at, uh, the rates of transpiration versus respiration. So, you know, if a plant is awake, if we say, um, it's going to be transpiring, right, it's going to be pulling CO2 and, um, stomates are going to be open. Um, if it's respiring, it's, it's actually going to be outputting CO2, it's going to be pulling in oxygen.
Jason [00:20:35]:
The stomates will, won't be open nearly as much as when we're transpiring. So during the day, uh, we're building those sugars, um, for, for plant growth. And actually when we're aspiring, we're going to be just using those sugars, um, for, for plant growth. So that's, that's kind of, kind of the basis of what we, what I know at this point.
Kaisha [00:20:56]:
Yeah. It's getting into the, more of the, the science behind the lighting. I love that. Thank you for that, Zach. We appreciate your question. Definitely keep us posted on how things are going. I am, we actually just got this question on YouTube, um, not specific to lighting, but it is talking about steering towards particular morphology. Richard asks, can you talk about the way that you would steer a plant that was more squatty versus a stretchy plant with environment?
Jason [00:21:23]:
Yeah, absolutely. And most who grows very many cultivars or a range of cultivars, strains, significantly different strains, they're going to encounter this where they know plants that they can't run very well in the room at the same time. So in my typical strategies for plants that are squattier, um, if I am trying to get a larger plant, usually I'll only do a very short amount of generative type of staring at the beginning of flower. So, you know, my, kind of, my favorite all time, um, example for this is Mac one. It's, it's typically just a real short, squat plant. And so for generative steering, I'll almost never run more than a week, absolute max for, for a plant like that. Really, our goal here is since the genetics are already generatively leaning, we're just doing a quick shot of, well, a quick burst of generative type of cue to the plant at the very beginning of flowers just to help get some amount of bud set and enable it for a pretty significant amount of bulking. Right.
Jason [00:22:30]:
Might even go six weeks, seven weeks of bulking depending on how it lands in our schedule. Really just to optimize, how much can we get out of this plant? If it's short and stubby, then we want to make it as tall and stubby, if you will, or tall and full as we can, just to get the most mass out of it. And vice versa with stretchier plants, you know, something like blue dreams. An example I've used quite a few times on the show here, uh, a plant that just seems like it never stops growing vertically, uh, a little bit harder, longer type of, uh, generative steering. So, uh, something like that, you know, we go four weeks of generative steering, maybe even a little bit longer. Um, and then another strategy that I was actually working with a client on a couple weeks ago was just running a little bit more balanced. Right. Once we talk about vegetative versus generative, it doesn't have to be, you know, one or the other, right? We can just, we can run it slightly leaning one way or the other, and that can help modulate some of these plants that have those tendencies as well.
Kaisha [00:23:39]:
Amazing. Great overview. Thank you for that, Richard. We appreciate your question. Thank you for dropping it on YouTube and let us know if you have any others. All right, we're going to keep it moving. We're getting some live questions in here. This one came through on YouTube from early Phi.
Kaisha [00:23:54]:
They wrote, I'm kind of confused about hot. You see media during flowers when it goes up to something like ten ec is 5000 ppm of nutrients available in solution to the plant. Seems really high when just comparing to individual PPM targets for individual nutrients.
Jason [00:24:13]:
Yeah. So basic question here is how high of nutrients is okay in flour? And it's one of the reasons that I absolutely love time series data because, you know, when, when we start to see our nutrients peak before our first irrigation of the day, um, some of that numbers may not really matter that much. Right. If a plant is only subjected to it for a really short amount of time, then, then it's not necessarily a great indicator of, you know, what our EC is in that substrate. Typically, you know, if we have a bigger change in that EC. So if we do see it spiking a lot of times, that can be a solution for generative queuing. Right. And that's kind of what we suggest when we're doing only p one shots, is letting our dry back and making sure there's sufficient nutrients in the substrate to stack it up and reduce osmotic differential.
Jason [00:25:10]:
So if I'm seeing ten ec while I'm running generative and I'm measuring with the teros twelve, for example, then I don't get too concerned at all. You know, actually, the ranges that I like to be once I've fully stacked and generative is, you know, seeing something like around, you know, seven or eight EC right after we irrigate and, you know, 1012, maybe potentially even just slightly higher when, when we're at, you know, our full dryback before the next day's irrigation. So, yes, you know, when we, when we think about it, that does seem high. Unfortunately, cannabis is a really hungry plants, and it kind of just depends on what, what are our goals at in this point of the cycle. If we are trying to be generative and have a low osmotic differential, then, you know, being higher up in those ranges is whats going to get us there.
Kaisha [00:26:05]:
Oh, now, our, our co host, Seth, just logged into the hangout. Wrote answer here, Seth, I dont know if you can unmute yourself. Can you unmute yourself?
Seth [00:26:15]:
Yeah, I can.
Kaisha [00:26:16]:
Awesome. Yeah. What do you want to add to that? Nice to see you, by the way.
Seth [00:26:20]:
Yeah, nice to see you guys. I was just interested. I heard Haley listening to it on Instagram, so I figured I'd log in. We're talking about, like, ratios of nutrients. If we're talking about PPM of nitrogen, calcium, et cetera. That's very different than when we're looking at the EC load in the substrate. And I think that's kind of maybe what they were asking if we wanted to have, let's say 600 ppm of nitrogen in a mix. Why are we suddenly up at 5000 total ppm? And we're talking about two totally different things here.
Jason [00:26:51]:
Yeah. And maybe I'll just chime in there. Yeah. It's one of the reasons I also always like to use EC, regardless of what I'm looking at here, simply because PPm is derived, EC is the measurement that's actually taking taken from a device that's looking at. So it's electrical connectivity. The more salts that we have in solution, the better that it passes an electrical current. And that's what most of the sensors are doing is taking a look at how well does electricity pass through the substrate or the solution. Depending on what we're measuring, it's what makes electrolytes.
Jason [00:27:28]:
When we think about, why am I drinking Gatorade? Well, because it's electrolyte, it helps this when we're looking at specifically ro water, it's not going to have any conductivity and that's why it comes through zero. So I like using EC just because it's a direct measurement. It's not derived like PPM in is. And PPM also has multiple scales. That's probably the one thing that I've seen a lot of mistakes been made over the years is we didn't specify, you know, if we were at the 500 or the 700 scale. And it's just one of those things we just don't have to do. Right. We can just.
Jason [00:28:02]:
There's just no reason to interpret it into PPm if we can run right off EC.
Kaisha [00:28:11]:
Right on. I love it. All right, cool. Well, we got both our guys on here. We're going to keep going. Let's see how many questions we can cover. But also just shout out, thank you, earlify, so much for your question. Moving on to this one from Tommy in the trees.
Kaisha [00:28:25]:
They wrote, I hear some growers do a 24 hours dark period when flipping from veg to flower. Are there any advantages or maybe disadvantages to doing that? What do you guys think?
Jason [00:28:37]:
Um, you know, I've heard of this and seen it quite a bit. Um, I personally don't, um, I don't necessarily think it's something that, that I like to do. Uh, it's just one of those things where, you know, maybe it's trying to indicate to the plant that we've changed. Photo period. Um, you know, the plants gonna feel that anyways. Uh, you know, especially if I'm going to be transplanting at the same time as I'm flipping the flower, I would definitely want to avoid it. Right. Uh, if I'm doing that at the time before I'm trying to get these specific rooting in practices going on or where I want root growth.
Jason [00:29:12]:
Right. I need to get this plant energy and, and keep it kind of on, on a schedule. So. So for me, I, I choose not to do it.
Seth [00:29:21]:
Yeah, we haven't really seen any evidence that there's a beneficial effect to having a 24 hours dark period. I think you, Jason, you're right on there. Like, there's a lot of belief, and, I mean, you can do this, right. If you put a plant in the closet and close the door for a few days, come back three days later, it'll probably start to have some pre flowering going on. But that's not really balanced. You know, if we've got a 55 to 60 day flowering time, a loss of 12 hours of light is still a significant amount of energy input missing out on and might be responsible for a very small percent of yield change. It's still one of the points where there's no reason to slow down the process.
Kaisha [00:29:58]:
Awesome. You guys rock. Thank you for that. I also want to do a quick shout out. Doctor J. 303 said, hi, Kaisha, on YouTube. Thank you for greeting me. Doctor J.
Kaisha [00:30:07]:
303. Hi, glad you're here. All right, you guys, we're going to keep it moving. We got actually a question from someone else named Seth who's on the hangout. He wrote, how do you approach changing your environmentals during transitionary periods between vegetative and generative steering? I've traditionally started warm, humid for veg early flower, and gradually gone colder, drier throughout the flower cycle. And I'm wondering if I should take a different approach. Thank you.
Jason [00:30:37]:
Yeah, so, great question. And this is actually one of the things that didn't come off to me as super intuitive when I started learning about crop stirring, and that is during our generative stacking. Sometimes I'll actually have a more vegetative feeling environment. So, like you're talking, during the first few weeks of flower, I like to have warmer temperatures, a little bit lower nighttime daytime differentials, and, um, and higher humidities. Right. Let's try and keep that VPD around 0.9. Um, that's just going to help some of this plant growth early on. But what we're doing is we're pushing really hard with some of that generative type of irrigations.
Jason [00:31:16]:
Um, so with the environment for the first three weeks is we're trying to optimize the, the rate of, uh, metabolism, the rate that we're getting transpiration the rate that this plant is growing. Right. And that's, that's just to try and optimize plant size. Um, and then we're kind of countering that. We're pushing with a generative type of irrigation to induce flowering and get, get the morphology right. Um, and then throughout bulking we, you know, we kind of compromise with the environment. And uh, that's going to be starting nighttime daytime differentials, um, and beginning to reduce the amount of humidity in there so we can get that VPD up to about 1.2. Um, and then into the cycle.
Jason [00:31:56]:
Yeah, we're going to be generative environment and generative type of irrigations for most strains. And keep in mind, we try to say this as much as possible. That is, our recommendations are always middle of the road. It's almost never that. And I get done with a client meeting and every one of their strains like the general crop steering recommendations that we have. So we just kind of use that as a general recommendation to, to give you a place to start playing with, uh, with some of the crop steering, um, tools that, that are in your toolbox and also just to use them as a representation of explaining how those cues can affect the plant.
Seth [00:32:36]:
Yeah. To answer the question real directly, you're, you're on the right page as far as starting off a little warmer and more humid and then we're going to cool it off and dry it out. And somewhere Jason's talking about, you know, compromising the environment a little bit in bulking. We might not actually run a super big cool diff, differential during bulking unless we're trying to, you know, slow down plant growth a lot. But that is the general thing. You know, we're starting out warm and humid. Basically, if it's too dry when you have small plants in the room and too cold, we're not going to get good growth throughout that generative period. So we want to get that humidity up, keep those stomata open until the plants develop enough leaf surface area to actually keep, you know, use transpiration to keep the humidity where we want it and start to have to dehumidify it.
Seth [00:33:16]:
And then as we go along, you know, later in the stage, especially ripening, we're going to want to run that overnight differential. We run a little cooler leaf temp during the daytime. And the hard, hardest part there is generally keeping your humidity in line. You know, usually we see it. I don't know, Jason, 80% of people we've talked to over the years, probably that's their immediate problem when they start crop steering is they put so much biomass in this room, they can't drop it down to that 65 degrees overnight, which becomes a pretty big problem. And that's where we start to see a lot of botrytis aspergillus, general bud rot. But, yeah, kind of made a long answer, an easy one here, but stay on that and probably, you know, keep track. Like we always talk about crop registration.
Seth [00:33:58]:
Take pictures of your plants. So you can really start to dial these periods of time for different strains, because different strains are going to need to have a longer or shorter generative period. Some are going to respond, you know, better to more bulking or worse, to more bulking. And those are the things you really need to keep track of when you're trying to dial this in. Because although we harvest our plants, you know, 55 to 65 days, each cultivar has its own slightly different timeline, and we try to group them the best we can. But 55 to 65 days, that's a manufacturing window. It's not, you know, catered to each individual cultivar. So the more you can pay attention and characterize what your cultivars are doing, the better success you're going to have in tuning your environment for crop steering.
Jason [00:34:42]:
Yeah. And actually, this is. I did want to wrap around to the question earlier, too. You know, he was asking about how do we, um, how do we steer strains that have other, you know, specific genetic traits that are either very generative or vegetative. And, um, you know, when I was talking about the ranges of going vegetative versus generative, um, even if, you know, even if we are pushing generative really hard and we need to go, you know, maybe we're pushing hard with generative irrigation. Excuse me, but we need to go even harder generative. That's when we can start to manipulate the environment. And so if our environment's vegetative and our irrigation is generative, if we start to tune that environment even more generative, then we're getting extremely far on the end.
Jason [00:35:26]:
So we already are kind of making some middle of the road compromises to optimize how we're getting this plant to represent itself.
Kaisha [00:35:38]:
Outstanding. Oh, Seth. Yes. Seth Wright, thank you for the clarification. I wasn't sure about having a generative irrigation while having a vegetative environment. You guys rock. You rock. It was a great question.
Kaisha [00:35:49]:
Appreciate you showing up and dropping that in the chat today. Awesome. Okay, we're going to change gears. Moving over to instagram. We got some live questions over there, so bringing it back to an earlier conversation from today's show, blossom grows, is asking, potassium silica versus MSA silica, does it make a difference? Guys, got any thoughts on that?
Jason [00:36:12]:
I'll let Seth start with this one.
Seth [00:36:18]:
I think a lot of it has to do with your water quality and how you're allowed to, or what your capabilities on mixing nutrients is. Silica generally is notoriously not well suspended in solution. It likes to fall out easily. And sometimes we see precipitation interactions with other nutrients and injection systems. It kind of comes down to one's goopier than the other, at least in my experience. And that, you know, it just depends on what kind of a system I'm running and what my capability is. So, like for that, I might mix up a much more dilute stock stock concentrate to inject. Just knowing that, hey, I'm going to have to inject a higher volume of this if I want my injector to work accurately every time.
Seth [00:36:59]:
And as far as plant nutrition goes, there might be some differences we can explore on, like, how that affects your nutrient ratios based on what you're putting in. But overall, it kind of comes down to usability and price. You know, if you. If you have one product that you're trying to add to a solution, but you can't get it into solution, it's essentially a waste of money. So that's. That's where I make the call. That's Jason.
Jason [00:37:22]:
You said everything more than I had.
Kaisha [00:37:26]:
All right, so it's about choosing your. Your goopy adventure. Fantastic. Thank you guys, for your insights on that. All right, good to see you, Seth. You had to hop off. I love it. Live streaming, y'all.
Kaisha [00:37:40]:
You know how it is. All right, we got this question from our good friend. Don't have a fold on Instagram. That's Manez from cookies u last year. He's asking, what irrigation controller do you suggest we use with your arroyo go system?
Jason [00:37:55]:
You know, with the AROYA go system, I'd probably go with open sprinkler. It's one of my favorites. Just because of cost, you know, it is a little bit hobby grade, but you can add some relays and a dedicated power supply and make it pretty solid. I've been running mine for a few years now without any issues. So open sprinkler is great because it does integrate right with arroyo, and you can start to build irrigation recipes. Aurora can automatically update your crop steering or your irrigation crop steering based on how you have your harvest group set up. So it'll have, you know, if you want to just run p one s during generative for the first few weeks. Then when it gets to vegetative, it can change the programs to what you've specified for week four and say, all right, now let's do some vegetative steering.
Jason [00:38:47]:
It'll add p two s in there automatically. Um, great way. Because it's accessible remote, you can do quite a few solenoids for a very cost effective price. And, um, and yeah, you know, it's a kind of one of those costs where it's like, easy to have a backup. Like I said, I, I haven't had any failures on, on mine. Um, however, some, some people, if they're pushing them too hard, trying to run too many channels at once, for example, they can get over current protection from that thing going on. Um, but, but I just work around that by making it only control relays. And so by far and large, that's what I would recommend to work with, is the open sprinkler.
Jason [00:39:28]:
And for me, it gives a lot of options to start playing with the software. If I need to do some specialized irrigation control, I can push to its API and specify irrigations based on other factors that are going on and, you know, outside of the arroyo system, for example, or, or outside of their specific programming allocations. It's just a really flexible unit. And, you know, for $150, you get eight channel set up. It can be run on Wi Fi. It's a pretty, pretty versatile unit.
Kaisha [00:40:07]:
Thank you for that walkthrough overview, Jason Minnez. We love hearing from our former students, so let us know if you have any other questions, but always great to hear from you. Now we got a question from a go light user. Kenobi dropped this on Instagram and wrote, I'm a go light user who hand waters. Are there good tips and methods to use to help steer? I'm using Athena and have been following their handbook for watering.
Jason [00:40:33]:
Yeah, you know, so, obviously the challenge with hand watering is, you know, how much time do we have to hand water? How many plants do we need to hand water in that amount of time? So we can run into a couple of concerns. One would be, obviously, are, are we running a large enough substrate in order to not have to have multiple irrigations throughout the day? Um, unless, you know, unless you're. That's all you have to do all day long is, is try and get, uh, irrigations to your plant. So really, you know, what's happening is if we go in a bigger substrate, then we can get away with just irrigating once a day. Um, that's going to kind of be a little bit more balanced or generative type of feeling. Irrigation. Obviously, the larger substrate means that we're gonna have slightly less dynamics and how much dryback we're getting and how much we can stack that Ec out quickly. So, you know, the best thing that you can do is try and get a process in that makes your hand watering as consistent as possible.
Jason [00:41:30]:
Well, or first as uniform as possible. Right. Have people that were like, you know, if it could be a timer or count in your head, if you can have a wand, hand watering wand that is fairly uniform and hopefully not as fast as flow rate as you'd like. Obviously, the faster you can irrigate which one, the faster you get it done. But usually the faster we irrigate, especially in a larger substrate, the more likely we are to see inconsistencies in substrate, water contents and ecs within that plant itself. So we get those irrigation channels, irrigation funneling in there as well. Yeah, those are all things to kind of consider. And, you know, for, for me, even on a reasonably small grow, the cost of getting some automated irrigation set up is well worth it in the, in the short run and in the long run, it's one of those things where one, it gives me more time to be doing things that are a little bit more beneficial to my crop.
Jason [00:42:35]:
Um, and it's going to make it so that I can do things, I can steer these crop in ways that I wouldn't be able to if I'm just hand watering.
Kaisha [00:42:45]:
Thank you so much, Jason. Yeah, Kenobi, great question. Welcome to the AROYA family. And, yeah, we just didn't overview about open sprinklers. So if you want to try some auto irrigation, maybe that's the way to go for you. So, yeah, good luck. Keep us posted. Happy growing.
Kaisha [00:42:59]:
All right, moving back to YouTube, we got this from Bangi Olipsen. I love this handle, but they wrote, hey, Roy, what temperatures would you go for with CO2 supplementation? What are the limits?
Jason [00:43:13]:
Yeah, so obviously, if we have the right amount of CO2 in there, in rooms with leds, usually all run up to 85 degrees early in the cycle or in veg rooms, as we start getting hotter than that, then we actually have a decrease in plant growth. Those temperatures. For led rooms that are optimizing plant growth, it's typically between 75 and 85. For hps, we're going to usually see it about three degrees lower. That's simply because the amount of far red, so the amount of solar radiation that is hitting the leaf surface because we're always trying to target leaf surface temperature even when we are looking at air temp. Really our goal here is to optimize the leaf surface temperature. And at that leaf surface, there's quite a few things going on that are changing its environment. Right.
Jason [00:44:11]:
So that transpiration, getting water vapor out of the stomates, that water vapor is going to be causing some amount of evaporative cooling on the leaf surface itself. And so most of the time, we'll see that the leaf surface a little bit cooler than the air temp. But in the case of nhps, where we are adding some heat to that environment from those far red photons, then we have to think about how much the environment's impacting that as well. Yeah, I think that breaks it down.
Kaisha [00:44:49]:
Perfect. Awesome. Thank you, Bangi, for your question. Our next question from YouTube comes from our good friend iron armor. They wrote, I noticed some strains, mainly in veg, start to lose turtle pressure a few hours before the light shuts off, while others don't. Any insight on why this happens?
Jason [00:45:10]:
Yeah, good old iron armor always loves questions. It could be a good number of things here if we're looking at substrate water content and substrate ecs. Are some of those plants just having some uniformity issues across the board, you know, clogged emitters and some of the ones that are losing tigger pressure are starting to start to see some temporary wilting point in those water contents. That's always a possibility. Some strain issues, environmental issues. It sounds like just some type of variable doesn't have uniformity in there. To me, that's probably the answer that that's right. Is find which variable isn't uniform.
Jason [00:46:03]:
So break it down and try and understand. All right, what's going on with the plants that are doing it. Is everything that I can investigate or measure the same with the ones that are doing it? The answer is, everything is the same. Then you kind of have to dig into some of the process controls, like, all right, was the clone cutting good or bad? Do I have some viroids in there? You know, that type of stuff? If the answer is no, then, you know, you found your variable that you got to dig into to improve.
Kaisha [00:46:36]:
Again. That's why crop registration is so handy, right? Being able to identify those anomalies. Yeah, go ahead, Jason.
Jason [00:46:47]:
I was just saying it definitely helps. The more that we can grab and document and make available for comparison, the better it goes. Um, you know, if last run, we only had 10% of the crop that was doing it. In this run, we have 30% we got to go back and look at what, you know, what, what happened between these two runs.
Kaisha [00:47:08]:
Got to do some detective work. Good luck out there. Iron armor. Always great to hear from you. All right. All right, we have about ten minutes left in the show. We got a couple great questions here on YouTube. Danny wants to know what's the deal with coco specific nutrients and should I use them?
Jason [00:47:24]:
Um, I don't actually, I'm not familiar with coco specific nutrients. I've always just used the same nutrients for coco or Rockwell. Um, so I I'd probably use something that's a little bit more, more mainstream. Uh, obviously, when we talk about nutrient, uh, availability to the plant, it's going to be related to those phs. Um, and then we also think about cation exchange capacity. Right. So when we are in coco, we have a little bit higher cation exchange capacity than we are in Rockwell. Rockwell is really low CEC, and thats why its kind of reactive.
Jason [00:48:04]:
When we make any changes to our fertigation levels, Rockwool is going to change pretty quickly. When were in coco, husk is actually hanging on to the particles in the coco, are actually hanging on to, uh, some of those nutrients a little bit. And so, uh, you know, if, if we're at the end of the cycle and we're thinking about running ro for a day, or hopefully not any more than that ever, uh, then, then the nutrient level in the coco and, you know, it may only drop, say, 25%, you know, depending on how much runoff we have, uh, it may only drop like 25%, whereas if we're in Rockwool, we're going to see a much larger change in that, in that level.
Kaisha [00:48:53]:
All right, well, Danny, I guess if you use some coco specific nutrients, we want you to report back to us, tell us how it goes, what you think about it, but, yeah, awesome, great. Thank you for that, Jason. All right, we got this question in from Kurt. They're a budget homegrower using HLG 100s. If they can only penetrate 16 to 18 inches, why grow them any bigger? What substrate size of rockwool and coco is ideal for this size when using substrate sensors? Two questions.
Jason [00:49:25]:
Yeah, so let's hammer out the first question real quick. This is kind of why the old sea of green growing thought came along, right? Was that, hey, we only have a short amount of canopy that can be utilized. And so, obviously, and when we're looking at a cannabis plant, for most cannabis plants, its typical morphology is somewhat bushy. We're like this. And so for only getting good quality and weight out of the top. 18 inches is what he was talking about in this segment. Then let's train them so that we have better horizontal canopy, more, more number of buds that are all at the same height in the canopy. You know, if you are very limited to how you do your, your plant deleafing, then, you know, a sea of green might be a good option if you only have 16 to 18 inches of light penetration, you know, and this also kind of comes down to why we see under canopy lighting as a really popular trend right now because we can grow a little bit bigger plant and make sure that we are getting light penetration throughout the crop.
Jason [00:50:39]:
One of the reasons that search green isn't as popular in production facilities. It's just really labor intensive and it's not necessarily optimizing the amount of not optimizing the facility that we have. It's going to be hard to get the same amount of weight out of a plant that we've trained to be flat on top, whereas one that is more natural in shape, if we can get light to that entire canopy on one that's in natural shape, one, we're going to have reduced labor and then two, we're going to have increased yields. So that's, that's what I see in the industry these days as far as how do we optimize that plant growth?
Kaisha [00:51:21]:
Amazing.
Jason [00:51:22]:
Kurt, question?
Kaisha [00:51:24]:
Oh, yeah. The second one was what substrate size of Rockwell and coco is ideal for this size when using substrate sensors?
Jason [00:51:34]:
Yeah. So something small. I mean, obviously if we're not building a. I typically like to be a four foot, five foot size plant. You know, sometimes, you know, if we're doing multi tier, we have constraints that, that dictate this. But, you know, usually you're going to be in a one gallon coco. If you're in a coco per rockwool, you're probably going to be six by six. Those are the options you have for a plant that's smaller.
Kaisha [00:52:06]:
Amazing. Yeah, no, this is good. Kurt, thank you so much for your question. Good luck out there. All right, we did do a poll on YouTube here. We asked how big is your grow? We got, 67% of respondents are coming in at less than 2000, are between 2000 and 5000 up. So we got some smaller grows. We are so glad that you are here.
Kaisha [00:52:33]:
Appreciate you checking out the pod. And yeah, to everybody on the show, this is a good one. We appreciate having you on. All right, this seems like a good one to close us out. This came in on Instagram. The real J 100 wants to know what's the best VPD for the best growth. So what are some considerations we can drop for them today?
Jason [00:52:56]:
Yeah, you know, when plants are younger. So through our, you know, our 18, six vegetative, we like to be at lower. Right. So when we think about the earliest, when we're, when we're cloning, we want to have a really low vpD. All right. We don't want to necessarily have a large amount of pressure deficit on these plants while we're just trying to get our root established and, and get it to have the, the supply lines of those roots so it can start to regulate how much water that it's losing throughout its leaves. Um, you know, so we're going to be pretty low through clone. Uh, as we're going to start, um, ramping up through veg, we'll, you know, moderately increase that.
Jason [00:53:39]:
Um, typically by the end of veg, I like to be in that 0.80.9 for vpD. And so by the middle of flower or even early middle of flower, I'll be up in that 1.2 range. You know, what, what my experience has been is 1.2 is kind of, kind of the ideal range for the bulk or the most of the flower cycle. And, and sometimes during ripening or even, you know, middle or middle end of the harvest group or the cycle. Well, I'll have to push them up to 1.4 and that. Yeah, that's simply if I'm running into molds, mildews, if I don't have good pruning practices or environmental consistency throughout my canopy, as I talked about, obviously in the canopy we've got a lot of transpiration that's adding to the humidity there. We are probably going to have less amount of airflow as well. So if you have a really dense canopy or if you have had issues with molds, mildews or strains that are susceptible to it, then I'll push up higher in that, say 1.4 range towards the end of flower.
Kaisha [00:54:49]:
Wonderful. Thank you so much for that, Jason. And then I just want to point out we have some. We have a VPD calculator. We've got great articles on VPD for the real J 100. So we got some resources for you so you can put it all together and enjoy monitoring your VPD over there. Let us know if you have any other questions. All right.
Kaisha [00:55:08]:
Well, Jason, with that, we're going to go ahead and wrap it up. Anything you want to say before we go?
Jason [00:55:12]:
Have a great day.
Kaisha [00:55:14]:
That's it. All right, y'all thank you Jason and producer Chris for another great session. And thank you all so much for joining us for this week's AROYA Office Hours. To learn more about AROYA, book a demo at AROYA IO and our team will show you the ins and outs of the ultimate cultivation cannabis cultivation platform. If you have any crop steering or cultivation questions you want us to cover, drop them anytime in the AROYA app. Email us at salesroya IO. Send us a DM on Instagram, Facebook or LinkedIn. We want to hear from you.
Kaisha [00:55:45]:
If we didn't get to your question, don't get discouraged. Keep submitting and we'll get to it eventually. If you're a fan of the pod, please leave us a review on Spotify, Apple Music, YouTube or wherever you listen to podcasts. We appreciate your feedback. Be sure to subscribe to our YouTube channel so you never miss an episode. Thanks y'all. We'll see you at episode 105. Bye.
Jason [00:56:05]:
It.