I'm reposting this here, cause it makes more sense. I don't mean to double post, it fits better in this topic, and I'd prefer this to have it's own thread. Originally posted in "Need Help With Autos?" This is a Swiss Cheese Feminized Auto by Nirvana. Roughly 7-9 week seed-to-harvest strain. All right. So, she's on day 22 from seed, (now day 23) and for the past week or so, the yellow has been creeping up. It first started at the cotyledons. They gradually started yellowing at the tips, and then became completely yellow. Right now, one of them is all brown, and the other is totally browned/almost black and all shriveled up. As you can see in the pictures, the yellowing has gone to work on the lower leaves. At first, I thought I might have been burning her with nutes. She seems to require water very often, as it gets relatively warm in my grow box, and I'm using mostly Light Warrior, which is very light & airy. It's roughly a 75/25 mix between Light Warrior and Ocean Forest. Both have premixed perlite. Anyway, soil dries out quickly, so she either gets a light watering every day, or a full watering with about 2 days of drying time after. And yes, I usually do a foliar spray each day, so perhaps I should back off on that. At any rate, I originally thought that nute-burn could have been precipitated by the frequent watering. So I flushed her, and watered with clean water for a few days.The problem persisted. I was never certain it was nute-burn, or anything. It was a guess. Back to research, again. I come across the diagnosis of Nitrogen deficiency, and I'm pretty certain that's what it is. What I've observed thus far is literally the textbook definition. Yellowing that starts at the lowest, oldest leaves, and slowly creeps up if untreated. So, I mixed up some new water. This time, with roughly half-strength nutes. (Humboldt Nutrients: Grow.) Prior to that, I was using less than 1/4. It was maybe more like 1/5-1/6. So, she's been getting 1/2 strength watering/spraying for the past few days, but the yellowing continues to worsen. Now, I'm almost certain this isn't the result of a pH problem. The water I'm giving her appears to be in the low-to-mid 6.x range. Testing with General Hydroponics test kit, I'm getting a solid yellow. I've also tested run-off water, same deal. Perhaps a bit lower. (The Light Warrior has humic acid, and it's probably preadjusted. But I know for sure, the Ocean Forest is preadjusted.) Unfortunately, the water I'm using isn't perfect. It's softened and highly filtered. So, I'm thinking of getting some Cal/Mag soon, as she likely wants some minerals. Could this be a secondary deficiency as a result of my too-soft water? Last thing I can think of, she was having some problems with heat stress, which would be mitigated by a watering. Like I said, it gets warm in my grow box. I was using 4 CFls, but now she seems less stressed under 3. At present, she's about 5 inches from the lights. I've got 1 intake fan and 2 exhaust. Sorry for such a long post. I wanted to be thorough. What would y'all suggest?
I think your problem lies in your watering habits. There is no way a plant that size in a container that size can actually need water every day or every other day. I suspect that over watering combined with foliar spray and the closeness of your lights is a big part of your problem. Using heavily filtered water is also famous for causing deficiencies. There are actually beneficial micronutrients in tap water that are needed by the plant in some degree throughout it's life cycle. Many who use RO water or something of the type end up with strange deficiencies that aren't normally seen on a regular basis. Use plain tap water. You don't have to let it sit out overnight because the treatment plants now use chloramine instead of chlorine. It doesn't evaporate nor is there enough of it in tap water to hurt your plants. I've been using it straight from the tap and pH adjusted for years now with lush healthy plants as a result. The pH range of any liquids going into your plant is critical as well as far as keeping it healthy. I tried to use one of the cheap drop kits for awhile only to discover that I was off enough to make a difference. The roots will lock up if you consistently use water/feeds that are out of range and not allow the plant's roots to take in nutrition...which causes deficiencies. I really don't think you need or have needed nutes to this point. The good soil you're using and the size container you started them out in made for a LOT of nutes in that soil naturally. The plant never needs nutes until it has had a chance to use up what came in the soil to start with. Soooooo....stop the foliar feeding/spray. It's something you do when they are very young and you're trying to up the humidity level to help them get rooted and there is no need for it now. Use tap water that is pH adjusted to a range of 6.3 to 6.7....for sure. Don't take chances with the pH if you want healthy plants. Since you've already flushed it, you're totally responsible for it's nutrition now. I suggest you read up on nutes and which ones the MJ needs and wants during different stages in it's life so you have a better understanding of what you really should be giving the plant and not just what the manufacturer suggests. Of course they want you to pour it to them because they make an INSANE amount of money selling that stuff. I stopped even using the combo bottle packs and started using Jack's by J.R. Peters. It's a simple 2-part dry mix, one part for veg and one for bloom, that mixes up just like Miracle Grow powder would. It's also super cheap. I can get enough to last me a year for under $20 and I flower between 20 and 25 a cycle. Keep on reading. Information is definitely your friend when first starting out. It's better to know it and not need it than it is to need to know it and not. Nutes can be complicated and a one-for-all recipe should never be expected to work. These plants will tell you exactly what you need. You've just got to be able to read what they're telling you. Happy growing! TWW
Wow. Thank you so much for the thoughtful, comprehensive response. I greatly appreciate it. What you've said definitely helps, and it very much lends itself to some of my predictions. I knew I had to be watering her way too much. It just didn't make a whole lot of sense, because she seemed to be wanting all that water. (Now, I think what she really wanted was minerals/micronutrients.) The water I'm using has to be the main problem. It's filtered so much, that it appears somewhere in the mid-to-upper 6.x range without any additives or pH adjustment. I'd venture to say that it has very, very little minerals/trace elements, if any. As fate would have it, I actually watered her with tap water just last night. And you know what I noticed today? It seems she's drinking it slower. I could be crazy, but I feel like the soil has retained its moisture more than it does with the super-filtered H2O. Just recently, I was reading that Calcium and other minerals/trace elements assist in the absorption of Nitrogen. Well, those things are missing not only from my water, but from my veg-nutes, as well. YES. This is exactly what I've been discovering very recently, and even more now. I actually received the Grow & Bloom nutrients as part of a grow-package of sorts. Well, there's a third one in the "Humboldt Nutrient System" that I'm missing -- "Micro." Not only does this Micro have all the good minerals/micronutrients I need, but I learned today THAT IT HAS MOST OF THE NITROGEN, TOO. That seems so backwards! It's gotta be a marketing ploy. So, pretty much, you can't buy one without the other. The "Grow" NPK is 2-1-6, and the "Micro" is 5-0-1. Am I missing something, here? Shouldn't the Nitrogen values be switched? Especially since you're supposed to use the Micro in tandem with the Bloom nutes during flower. And as we all know, the flowering stage requires lower amounts of Nitrogen. Doesn't really add up, to me. So yeah, I was pretty much forced to Amazon the Micro today. It was obviously designed to fill the deliberate nutritional gaps in the Grow & Bloom nutes. Bastards! Haha. Anyway, thanks again for all the advice and the thoughtful response. From now on, pH'd tap water!
All right, I'm just about at wit's end, here. I've got maybe a few more tricks up my sleeve -- long shots, really. After that, I'll be out of ideas. Day 27, and she's gotten significantly worse. The yellowing has accelerated with browning, and now, she's been presenting with Phosphorous deficiency, which is not good. This is seeming a lot more like a nutrient lockout, now. My best guess is that the main problems are at the roots due to my excessive watering. (Where before, I thought it was a lack of minerals/trace elements/nutrients.) I'm praying that some Hydroguard will begin to straighten things out. More, later.
Only real way to get a grasp is a GOOD PH meter. I suggest Bluelab but they are expensive but all their meters are worth it. Have pics of plant now!?
Yeah... With the way things have been going, I'm starting to think I had a false sense of certainty regarding pH. The color I was getting seemed to indicate I was right on the money. Though, I suppose I have no way of knowing how accurate this drop-test is. I would love to have one of those fancy, actually-accurate digital pH meters, but I can't justify it right now. I've poured SO much money into this already, and I can't imagine my test kit is that inaccurate. If anything, I feel like my perception of it, is. At any rate, I'll continue with the update. [Day 28] Her decline continues to accelerate. One of her leaves is now dead. It's very crispy, darkened, and totally wilted. Many more leaves are taking on symptoms, displaying a lack of both Nitrogen, and Phosphorous. (Though, the Phosphorous problem seems a lot more aggressive. It started only recently, and has done more damage, much quicker.) The bud-sites still appear fine, but at this rate, I'm starting to doubt she'll make it to harvest if she doesn't start getting better soon. It breaks my heart. I just received my Hydroguard in the mail, today. Soil was sufficiently dry & loose, so I mixed in the proper amount of Hydroguard with my nutrient solution, and gave her a drink. From what I've seen around the internets, it seems this stuff has been a real saving-grace for people with root problems. In addition to that, I actually tried some pH up, for a change. I figured I'm not having any luck with adjusting it down, or leaving it as is, so I might as well try bringing it up. (Water already appears acidic before any adjustment.) Also, according to various Cannabis nutrient-uptake charts, Phosphorous is best absorbed in soil above 6.5 potential Hydrogen. Right now, I'm starting to hypothesize that the root environment is actually too acidic. I just reread the instructions for this particular pH control kit, and I'm starting to think my initial perception of color-to-pH was a bit off. I'm not saying I might perceive color inaccurately, but that perhaps my gauging was off. That I was perceiving the pH value, higher than it actually was. I'm now thinking it's possible she was getting water as low as roughly 5.5, and only as high as roughly 6.0-6.2. The runoff test I did, presented even slightly lower than the input water. Hah, jesus. I feel like Dr. House with all this. Really hope I'm on to something, though. If so, it could explain a lot. Perhaps I'll post some new pics tomorrow, or with the next update. Thanks to anyone who reads through all this. I greatly appreciate the input!
Please help! She's dying. [Day 30] OKAY. I swear, I've tried so much. And, I've put so much effort into intuitively discerning the underlying cause, and I've done so much trial and error. It's like, NOTHING I DO helps. On one hand, I'm wondering if what I've tried is actually making it worse. But, on the other, I feel like, if I just back off and stop playing doctor, that she'll just decline that much faster. I don't even want to post pictures because of how depressing it is -- seeing her health get worse and worse every day. I hate it. It kills me. Like what the fuck. I know it's my first grow and everything. And, not everyone is going to succeed, their first time. But, god. I thought I had this in the bag. I've done an obsessive amount of research, and I've done my absolute best, here. This is incredibly disheartening and defeating. I'm still going with the pH idea. Since that seems to be the biggest, most common cause of nutrient problems. But now, I'm also wondering if there could be a buildup of nutrients/salts or whatever causing the lockout. God, this is so frustrating and incredibly difficult. I feel like I'm looking for a needle in a MOUNTAIN of hay. Yes, a mountain. Roughly the size of Everest. Anyway, do you think that could be a possible cause? A buildup, of sorts? Should I flush her? It's just... I kind of doubt this to be the case. She's not that old. I mean yeah, I have been using nutrients a lot. Like, pretty much every time she gets watered, but the problem first started either before any nutes, or when I was giving her very, very low doses. Aren't you only supposed to feed with nutes like every 2nd or 3rd watering, anyway? Even in flower? Anyway, I'm probably going to try no nutes for the next watering. Just pH'd with Hydroguard. I could really use someone's input right about now..
These two pictures were taken just minutes ago. As you can see, even the higher leaves are displaying symptoms, now. I'm desperate. Please, someone help.
No, I do not. As stated above, I'm using the General Hydroponics pH Test Kit. I've covered something of a pH range, though I'm only now starting to experiment with more alkaline water.
The strips and GH are not going to get you what you need. To really grow w minimal hassle a good PH tester is a must. I'm guessing you will still have problems without a tester. I've seen GH kit range so widely depending were soil is taken from within same pot. My 2¢
[Day 32] On day 30, I gave her a flush, and switched half of the lights to 2700 K. On day 31, I switched the other half, but the lights aren't the point, the flush is. After inspecting her today, I think the flush really started to do some good. And not only that, but I have yet another addition to my ever-evolving theory. I believe I had been watering incorrectly, but perhaps in a different way than The Widow White suggested. Of course, I still believe her to be correct, but missing a vital piece of information. She's right. There's no way a plant this size could have kept up with how frequently I used to water her, but that assumes I was giving her the right amount of water. I wasn't watering until much, if any runoff occurred. That, along with my super light & airy, fast-drying soil, and very small growing container = nutrient problems. I almost never saw drooping/signs of overwatering. Because, yes, I was watering too frequently, but that's because I wasn't giving enough<span class="redactor-invisible-space"> water per drink. In other words, they were incomplete waterings</span>. Everyone says to water until about 20% of the input water drains as runoff. Well, I never did that. I don't know, it just didn't seem incredibly necessary or crucial, but I see now, that it definitely is. Flushing her properly this time, has been the FIRST time anything I've tried has actually helped. So, I'm thinking this is less a problem of pH, and more a problem of incorrect watering. SO. I'm going to flush her one more time (probably tomorrow) with quarter-strength nutes, and then continue with half-strength feedings every other watering -- this time, with proper runoff! I think this sounds like a good plan. If anyone has any other advice, please share. Thanks.
So, I guess this is turning into more of a grow journal, ha. Oh well. [Day 34] Flushed her again, yesterday (day 33). This time, I tested the runoff pH, and confirmed one of my hypotheses. Test came back orange, which would indicate a pH low for even the HYDROPONIC range. Somewhere in the low-to-mid 5.x range, I surmise. Crazy, right? I don't even know how it got that acidic. Either way, this is a huge<span class="redactor-invisible-space"> relief for me, 'cause I think I finally figured it out. Once I saw that, I began to incrementally add pH UP to my flush solution, and continued to flush & test. I knew I'd be risking a stressful pH fluctuation by doing this, but I figured the benefits would greatly outweigh the risk of pH shock. Besides, I wasn't gonna let her go another minute in that harmfully-acidic root environment. And, from what I can discern, this has done much good for her. Even after the first flush, I noticed accelerated new growth, but now, even more so. Her leaf growth had really slowed down before these 2 flushes. The older, bigger leaves even fell off, but now, the newer fan leaves are coming in pretty nicely. Despite flushing her twice, now, she hasn't showed any signs of overwatering, which I am most grateful for. I must say, the Hydroguard has really given me peace of mind for each and every watering. Not that it prevents overwatering, obviously, but it most certainly prevents, even reverses root rot, amongst other great things. I'll never water another plant without it! The development of her bud-sites has also<span class="redactor-invisible-space"> revved up, which I'm thrilled about. Things were looking pretty dire, there, for a while, but her new development seems promising. She's not out of the woods just yet, though. I'll feel more confident about that</span></span> when I can test her runoff, again. Saving the best for last: She's got some trichs, now! I was most please to see that. It's not much, yet, but it gives me hope for her future.
[Day 35] Yes. She is much better, now. I just inspected her, and I must say I was impressed with the development of her new fan leaves surrounding the bud-sites. So much new healthy green coming in! I'm super relieved to say the yellowing & browning from the nute-lockout has halted. The affected leaves aren't really getting any worse, which is great to see. Before I started flushing, even the new lowest leaves started to turn a pale green from the transference of Nitrogen, but that has effectively stopped. The reddish-purple running up the stem is still there, so I don't know if that's permanent or not, but she seems to be doing fine, regardless. Anyway, I'm just really happy to see that she's getting a lot better. Definitely more trichome development taking place throughout more of the bud-sites, so I'm stoked to see that. Also, her scent has started to come through noticeably more in the past week or less. She smells enticing! Though, I've read that this particular strain becomes extraordinarily pungent in full bloom. Like a peppery cheese, which should be interesting. Been smelling the pepper-like aroma for a while now. Soil is still plenty wet from the last flush two days ago. I estimate she won't require any more water for another two days or so. Thinking about maybe doing a little LST, soon -- see if it helps any. Also, the next time she gets fed, it will be with a nutrient ratio more in favor of bloom nutes. But worry not, she'll still get plenty of Nitrogen. But yeah. That's my update for today. Excelsior!
[Day 37] Unfortunately, some of her problems started coming back in the last two days. I would have liked to wait a bit longer before watering again, but I knew another pH adjustment was necessary. Some of her lower/young leaves developed some spotting from what would seem to be a continuation of Phosphorous deficiency. I've also noticed what would appear to be something of a calcium deficiency on the already-fucked leaves. Also, some of her higher leaves seem kind of pale. Tested her runoff many times today. It was quite the flush, as I had to keep adding pH-up to my flush solution. This time, 1/5-strength nutes. First few tests came back orange. Had to use a lot of pH-up. Much more than I would have liked to. I know it can take a lot to stabilize pH, but this soil seems stubborn. Either way, I finally got it to the range I'm looking for. 6.5 to 7.0. Really hoping I won't have to do any more drastic adjustments like this. I'm a little worried about how she'll react to all this, though it seemed to do a lot of good, the first two times. I guess we'll see. Other than that, been noticing more trichome development consistently each day. Always happy to see that. 'Til next time.
[Day 38] Eff. It would appear that she worsened since yesterday. Both in the apparent Phosphorous and seeming Calcium deficiencies. I know it can take a few days to recover, but I was hoping it would at least slow down with the pH adjustment I did yesterday. Just learned that wet & compacted soil can cause P-deficiency. That definitely explains it. These flushes have certainly made the soil much more compact. In other words, while fixing the problem, I created another one. Great. Oh well, if that is the cause, (and I'm pretty sure it is) then it should start to clear up in the next few days. I swear, it's like no matter what I do, there's always SOMETHING throwing her off. At least I'm learning and internalizing this process, but Jesus. I feel like most other plant species aren't so goddamn temperamental . Though, I wouldn't know from experience. I know it's called "weed" for a reason. Because it grows relatively fast and, they say it's resilient, but I feel like it's not really that resilient. Like, yeah it's good at CANNAbalizing itself to protect her flowers at the expense of her foliage, but it seems once the damage is done, it's done. Anyway, I'll attempt to loosen the soil a bit, so it can dry faster.
All that flushing takes EVERYTHING beneficial from soil. So plant is starving of course it will show symptoms. You can overdo flushing, also it's a one shot thing don't flush days in a row. Put 3:1 water to container size through it, also you don't have to keep ph adjusting each time in steps. Ph water t 6.5 and pour through, measure runoff repeat. Cannabis is nothing like a weed it's like a tomato. Also after flush it's good idea last water you add is 1/4 strength nutes and you give it a few days to dry out and recoup. Flushing stresses plant so a day or two isn't going to show a gorgeous healthy plant.
OP, not sure if you've been asked or if you've addressed this or not... But what is/are your relative humidity and ambient temperatures? I'm currently having issue trying to connect to a link that explains vapor pressure deficit and why it's so important for proper nutrient uptake by plants. I'll try again later... In short, when air is hot and dry leaf stomata close to preserve cellular moisture. Plants absorb CO2 through their leaf stomata. They also expel oxygen and water vapor through the process of transpiration. CO2 drives the photosynthetic process, which in turn drives all plant metabolism. No photosynthesis, no (or at least very little) nutrient/moisture absorption through the roots, and no growth... Edit: Here's that link... http://www.just4growers.com/stream/temperature-hum...
Hello, peoples. I greatly appreciate the responses -- thank you. @NaturalMistik Thanks for the advice. I knew I was really pushing it with these flushes. It was a gamble, and one that I lost. I just wanted to fix the soil pH once and for all, because I was so fed up with nothing working. Turns out, I overdid it. Used too much pH-up to adjust faster. The runoff would barely change if at all when I'd flush with target-pH water. Yes, I agree. I should have been more patient. I just didn't want her to keep getting worse at the rate she was, so it felt like a drastic measure was necessary. As a result, what I originally perceived as a lack of Phosphorous & Calcium uptake, was actually the result of this dramatic pH upswing. @waktoo I find this information highly-valuable. Thanks for the link. Just read through all that and bookmarked. Unfortunately, I haven't been actively monitoring temperature and relative humidity, for there is little I feel I can do to affect either. Though, I'm realizing now that if I can do anything to influence it positively, that I should. My RH is most likely lower than it should be. Not sure what it is exactly. Been meaning to get a decent hygrometer. The temperature should be within range. Maybe a little warm, but it should be within an acceptable range. Once I obtain a hygrometer, I'll post RH and temp.