This is my 2nd grow and I’m experiencing an issue that shows signs of being nitrogen deficiency and toxicity. I’m using nutrient rich soil on the bottom 1/3 of the the pot and a regular pot growing soil on the top 2/3 of the pot. I’m growing 6 plants and this one is the only plant with this issue. I haven’t giving nutrients besides what came in the soil. I’m watering with a PH between 6.0-7.0. The lowest leaves starting turning yellow a few days ago. The veins stayed green, but the rest was yellowing. Yesterday I noticed some brown spots on the yellowing leaves and today those same leaves are very yellow and brown. I now notice the leaves above the yellow ones starting to show early signs of yellowing. From the research I’ve done, this is a sign of nitrogen deficiency. The a lot of the leaves on the whole plant are clawing, which I initially thought was N toxicity, but now I think it’s something else. I have been watering daily so maybe overwatering?
Sounds like overwatering if you are watering every day. Too much water can cause symptoms that mimic deficiencies in the soil. There is typically more than enough nutrients in the soil, but the plant can't absorb them. The roots can't breathe, and if left long enough, the root hairs will die, and eventually the main root will rot and die. Basically the same thing that happens when an air pump shits the bed in a deep water culture setup. The problem then becomes that the new grower wants to "fix" the plant by applying more water and/or fertilizer, and then chokes the roots for another few days, and the plant translocates even more N, P, or K or whatever nutrient it needs from its own self, usually the lower leaves, for survival, and to help it build new roots. If you keep watering, the healing takes longer and longer, and can eventually cause other "deficiencies" to rear their ugly head. Important: - let the plant have more of a wet dry cycle, it has to breathe - when you do water/fertilize, always apply the water until you see runoff out the bottom of the pot Optional: - I prefer to fertilize every watering, even if only 1/4 strength or less
Why not get a veg nutrient ? Feed it. A clue to you . The bigger plant is having more issue then the others . The plant used up all the nutrients available in the soil. I suggest putting them into larger containers then start using a veg nutrient . This will solve your problems . Also i see a bit of cupping on the left plant in the pic and slight in the others . Raise you light a few inches . For the over water post . Watering Your Cannabis: How To Fix Over And Underwatering - RQS Blog Also nutrients are fed many different ways. This is a active debate by many growers when and how often to feed nutrietns . Around here we feed full strength nutrients every time we water . How do you know when to water . Pick the pot up feel the weight. I have a fucked back and some of the pots are 20 gallon containers . I stick my finger in a inch deep if its dry i water . I will add enough water to soak the entire pot . 5 gallons typical half gallon of water actually a bit more added every time . Edit use perlite. You can not over water its basically impossible . The excess water will just leak right out of the pot to be wiped up. I suggest for you 50/50 perlite to soil . You will never have another over or under water issue again . Use the fine perlite . And for how often you might need to water will vary from every day to every 4 or 5 days .
It happens. I agree with most everything you said, except for the fine perlite part. I have always found fine perlite ends up like concrete by the end of a cycle. Coarse and super coarse help prevent that by being better at resisting soil compaction. Same principle as why Hempy bucket growers prefer coarse or super coarse perlite, and always wash and soak their perlite, before use. To get rid of any fine stuff and the dust that makes that paper maché like paste.
Yes, Very likely N def. Classic tell is otherwise healthy plant going yellow from bottom up. Good news is it is very easy to fix and plants respond sometimes in less than 24 hours. Something like Dyna-gro Foliage pro at 4ml/gallon at proper ph will correct that problem, or any liquid fertilizer with an N number.
I agree with you . Not all perlite is the same. If you talking about that sand perlite . I was not talking about that. I was suggesting the perlite size most soils come with already . The store i go too has 4 different kinds almost sandy . Same as what is in the soil already. 5 Times as big . And stupid big as a stone .
Aaah yes, very true. Yeah the fine stuff from the brand I have access to is rather dusty. I could probably mortar brick with it lol!
Thank you so much and sorry for my late reply. This was very helpful. I transplanted into a larger pot 4 days and and have been watering less. The issue is still present and now spreading to the leaves above. I haven’t been using nutrient because I was told that this soil I’m using is basically super soil and it didn’t need nutes. Obviously I’m deficient in nitrogen now so I’m going to put some of that in and maybe feed nutes going forward.
Thab Thank you so much. I’ve modified my watering now and it the yellow and browning leaves have spread to the set of leaves above the ones that were affected before. Going to add nitrogen now
Cool. Yeah as long as you follow those basic watering rules, then at least you can eliminate those as the source of the problem. Learning to water to runoff, and then let it dry a little before watering/feeding again made a huge difference in the quality of my "soil" plants vs trying to simply maintain a certain level of water in the medium. But yeah, it does sound like you need a little feeding if it's progressing further and you aren't still hammering water into it.. The beauty of N deficiency, if you can call it beautiful in any way, is that it does tend to fix quickly as it's highly mobile in the plant. Best of luck
I have an update. I went to a hydroponics shop yesterday to buy some nitrogen and the guy who was helping saw my photos and swore up and down that it’s not a nitrogen issue and that he’d just cut those dying leaves off and not feed the plant any nutes. I had purchased the soil from them so he knew exactly what I was using. He said that it’s nothing to worry about even though I told him that it’s spreading upward. Now I don’t know what to do. I kinda don’t believe him, but at the same time I’m new to this so I don’t know. It just seems like it matches up perfectly to n deficiency except for the few burnt tips and the clawing leaves.
Yeah I'm not sure what he means. "Nothing to worry about". I don't know about that. I don't know what his thoughts are on the cause. Are you sure what he said? Did he say "don't feed" or did he say "don't water"? This might help clarify what his idea on what the cause is....maybe. Burnt tips and clawing leaves can be a sign of over fertilizing, too. You may have too many salts and it's caused an alkalinity issue, locking out a nutrient, maybe swinging the pH too much. Sometimes an over abundance of one element can cause lockout of another element. This can be an issue too. I dunno if anyone suggested a slurry test and /or a runoff test. That might be something to do to at least eliminate pH or TDS/ppm/EC as the issue.
He definitely told me need to feed it anything but plain water. I tried to tell him that I thought it was a nitrogen issue, but he said no. He told me the same thing that the burnt tips and clawing meant that it got too much nutrients. He said that the plant it used to it at this point so don’t worry. I have not tested the runoff ph or the ppm. I don’t even own a ppm meter but plan to buy one shortly. My ph pen broke so I’m using the type where you put drops into a cylinder and check the color. Not as accurate, but it still shows me that I’m between 6-7ph when watering.
When you water and it comes out the drains and into those Tupperware containers, do you get rid of the standing water or let the plant sit in it and soak it back up? Soaking it back up probably isn't the best idea because you can salt load the bottom 1/3 of the plant and cause issues. Just wanna make sure that isn't something else giving you grief.
I drain it for sure. This is my 2nd grow. I learned last grow how it’s important to drain the water. Last grow I used coco and mixed my own nutes. This grow is my 1st time trying nutrient dense soil. I had read somewhere that you don’t want runoff when growing with a super soil. Is that true? when using coco I made sure to have significant runoff every time
You want to make sure the entire pot is saturated evenly. The easiest way to do that is with a nice even watering up top, and a little ooze out the bottom. But yeah, with a super soil, you kind of take it a little easier. Don't runoff like you would coco. Many people don't even do a final flush with organics, I never did. Eventually, you start to figure out your mix, and how much it takes to get the pot/s properly soaked and oozing a little bit, without overly excessive runoff.