Nitro Toxicity :(

Discussion in 'Growing Marijuana Indoors' started by Bigaveli, Aug 14, 2018.

  1. Hey guys, long time lurker, first time poster here. Really appreciate the community on these forums, they've taught me a lot.

    I'm in the middle of my first indoor grow, 2 fem OGK plants in an organic "super soil" I blended myself. Maybe 8 weeks from seed in veg. These girls were preforming FABULOUSLY throughout this whole grow, no nutes, nothing, just LST, topping, and light waterings every few days.

    Then about about a week ago I came across a 8-0-0 fertilizer in my shed and figured hey a little N won't hurt right? Should give them a nice little boost. So I foolishly mixed a full strength, perhaps a little over, batch and fed them to my plants. They did not respond well.

    A few days later and I notice the typical Nitrogen clawing on the older leaves and some pretty nasty burns and curling tips on some of the newer growth. The new growth is coming in a much lighter green and are canoeing like crazy. Their tips also burn and curl up before they get a chance to mature.

    I did a light flush 2 days ago, and I'm thinking about doing another one in a day or two when the soil is nice and dry.

    I was planning on transplanting them into 7 gallon smart pots and going in to flower this week but I've been advised to hold off at least 3 weeks before doing that due to the N toxicity.

    I was just hoping for some advice from someone who has dealt with this before and managed to recover and still harvest a decent crop.

    Should i transplant them and then give them a serious flush? They seem to be doing A LITTLE better after the first one but it's hard to say. Growth is definitely stunted rn.
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  2. That sucks man I had light nitrogen toxicity at the beginning of my current grow. I flushed and it was stunted but she survived. Idk how much more you will want to stress the plant. If the leaves are continuing to curl and the burns worsen then I would agree and do a serious flush.
     
  3. if it was a liquid fert, I would flush the soil a couple times.
     
  4. Yea I'm gonna see what happens over the next few days and then proceed with a flush like storz suggests
     
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  5. I would pot up too soon. Might be a bit rootbound? What size is your pot?
     
  6. It's a 2 gallon pot but it hasn't been in there for too long and the roots don't seem to have reached the bottom or outskirts yet
     
  7. I would argue that is not nitrogen toxicity. It doesn't look like it to me. It looks like P&K burn or too high of temps.

    Both conditions would require a flush but nitro toxicity is very dark green color, waxy appearance to leaves, and a downward curl to the leaves or the "claw" effect, almost like overwatering.

    Your tips are curled up not down and it's not very dark green at all. Something going on but it's not too much nitro.

    Flush it good and come back with a lighter mix of nutrients then you were feeding. If you can figure out how to get your NPK numbers balanced and controlled with what you're using try for a 5-10-10 NPK ratio or 1,2,2 depending on how you look at it. That's the most successful feed ratio for cannabis in hydroponics.
     
  8. I take that back with a second look. I do see light nitro toxicity but there is other stuff going on as well.
     
    • Agree Agree x 1
  9. Any tips on flushing? Just soak the hell out of it and let it drain?
     
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  10. Yea its just strange that this came outta nowhere after a feeding with an 8-0-0 liquid fert, perhaps it caused some kinda lockout?
     
  11. Usually the runoff coming out of the bottom of the pot when flushing will have some color to it. You can watch for it to clean up and start running more clear. You can make sure about a quart to a half gallon makes it out the bottom and call it good.

    After the flush give it a 2 days to dry out then feed it again but weaker then before and more balanced. Why feed just nitro. The cannabis plant likes about twice as much phosphorus and potassium on average compared to nitro in it's feed. You need almost as much calcium as nitro. Around 5% of feed totals.
     
  12. The order of consumption of plant feed in amount goes like this for cannabis.
    1. Phosphorus. A cannabis plant will eat more phosphorus during it's life then anything else.
    2. Potassium
    3. Nitrogen
    4. Calcium
    5. Sulfur
    6. Magnesium.
    7. Iron

    After iron they are basically micronutrients needed in amounts less then .1% of feed.
     
  13. I see, yeah best of luck man I hope she bounces back.
     
  14. Yea it was a pretty stupid idea looking back, especially seeing as it was doing so well in the soil I prepared for it. I should have waited to see any sign of deficiency before giving a real balanced nute.
     
  15. Good info here, noted.

    I appreciate it man, I'll keep you guys posted
     
  16. go ahead flush the hell out of it even put new soil in throw it into a lake. and in a few weeks 2 or 3 later this plant will be dead. are you on here telling us you refuse to get a better nutrient? if so let us know ill just put you on ignore so when you post for more help later i will not see it wasting my time.
     
  17. That's not what I'm saying at all. Just that I wish I hadn't bothered with nutes at all rn as the soil was providing for it so well. Don't fix it if it ain't broken kinda deal. Def plan on getting some decent nutes, especially for flowering.
     
  18. Check the pH of your run off water when you flush. That could also be an issue.

    Sent from my ONEPLUS A3000 using Grasscity Forum mobile app
     
  19. Before I started my first grow, I read an article on growing and the author said, "Most cannabis growing mistakes start with, 'I wonder what'll happen if I..."

    For me, that has proven to be 10000% true. lol
     

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