Learn To Spot Phosphorus Deficiency In Cannabis

Learn To Spot Phosphorus Deficiency In Cannabis

Today on Lex’s World I give you guys pointers on Phosphorus deficiency, also known as P-deficiency. If you are in flowering, are seeing purple stems and beginning to see black blotches on your lower leaves, this is probably the video for you.

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My old episode on N-deficiency: https://www.bitchute.com/video/XekIMsiVJg5o/

My old episode on Mg deficiency: https://www.bitchute.com/video/Mt4nRRpYaZ24/

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50 Comments

  1. Richard Deutschmann on June 14, 2022 at 10:51 am

    I think y meant raise you PH so it can take up mor P?



  2. Amknox on June 14, 2022 at 10:53 am

    your the best



  3. Get Rekt on June 14, 2022 at 10:55 am

    fuck shit what if it starts at the top



  4. Magic Big Beans on June 14, 2022 at 10:55 am

    Hi Lex Blazer, I am a noob and I have similar looking problem with the leaves I have a pH of 6 to 6.5 and when I water through soil and it drains out the pot the water drained tests at pH 5. Should I increase my water pH or is this normal?



  5. JackalXD on June 14, 2022 at 10:57 am

    So can you check soil ph the same way as hydro ph?



  6. Mike on June 14, 2022 at 10:57 am

    I like that deficiencies chart where can I buy it at..🙏



  7. Stephen Rooney Photography WA on June 14, 2022 at 10:57 am

    Thanks for sharing



  8. Janel Holmes on June 14, 2022 at 10:57 am

    Thank you 🙏🏻



  9. Flummy Tommy on June 14, 2022 at 10:59 am

    Tips on Germany plesse



  10. Bradley on June 14, 2022 at 11:01 am

    My friends greenhouse gets cold at night with no heater inside, she never has any problems, strange.



  11. Tim Page on June 14, 2022 at 11:04 am

    Alot of phosphorus deficiencies come about because the ph of the soil becomes acidic after time.
    Example last grow I was putting in nutes at ph of 6.4 and it was coming out at 5.2 .
    Check your ph people in a slurry test often.



  12. Phenom on June 14, 2022 at 11:04 am

    You hit the nail on the head. You described my problem perfectly and your pictures are accurate. Everyone I asked for help told me it was cal mag deficiency.

    Thanks for your help!



  13. Al D. on June 14, 2022 at 11:06 am

    Looks just like magnesium deficiency.



  14. Rob DuBois on June 14, 2022 at 11:07 am

    How do i drop the PH of soil? Do I just water the soil with PH balanced water?



  15. ice man T on June 14, 2022 at 11:07 am

    Hey I just started growing my plant I’m now 3 months in and I’m getting all these signs but I’m in veg stage I have all those dark spots on my lower leaves the stems are also purple but I have a bloom and grow fertilizer my house stays at about 73 degrees it’s been growing well I had some yellowing early in the process but when I just gave my plant water it seemed to nurse itself back to health I dont know if I should keep giving it the grow fertilizer ever 2 weeks or should I stop and just water it normally please help I’m very new to growing btw I did a quarter if a teaspoon of grow fertilizer to a gallon of water is that not enough or should I do more I know in the video he said purple stems could also mean jnderfeeding I’m using miracle grow soil yellow bag because I couldn’t afford anything else PLEASE HELP



  16. Get Rekt on June 14, 2022 at 11:09 am

    my plant is rusty but its only happening near the top i had low ph (5) now im up to 7



  17. Circle on June 14, 2022 at 11:11 am

    The image at 3:08 threw me off compared to what you’re saying at the time. You said you pH (in hydro or soil) is probably too *high*. But the diagram for hydro shows that Phosphorus is available from 5.8 *up* to 6.1. And that Phosphorus isn’t available at all below 5.8… So I’m a little confused.

    Could you clarify on this please? There’s so many of those nutrient availability charts too.
    Thanks.



  18. afili8ed on June 14, 2022 at 11:12 am

    Thanks man! Good video. I’m dealing with it rn. It’s not too bad if you catch it, they recover nicely. Appreciate the information. 💪👍



  19. Tim Sanders on June 14, 2022 at 11:13 am

    Thanks Lex



  20. saint 85 on June 14, 2022 at 11:14 am

    What about any dry amendments Can you recommend any dry amendments growing organic soil it’s figured I ask you know what I can add for that



  21. Thirty Eight on June 14, 2022 at 11:16 am

    thanks Lex



  22. Nate Ellenberger on June 14, 2022 at 11:19 am

    This was a major score for me watching this video. I’m a beginner grower with only 3 successful harvests (all 3 have been magnificent and produced a better product than I was use to buying for years). With all 3 grows, I haven’t had any major problems except for a few leaves turning yellow, hear and there, and my stems turning slightly purple. It was like clockwork with all 3 grows when the problems starting occurring (yellowing leaves about the 2nd to 3rd week of flowering) and all 3 grows were different strains/types of pheno’s. I used the same feeding schedule for all my grows so the yellowing leaves (like clockwork) is something I’m doing wrong with feeding/watering. I originally thought the purple stems were just part of the plants natural color, but by watching this video I’m learning the yellow leaves combined with purple stems is a phosphorus deficiency. It makes perfect sense because I’m using Advanced Nutrients as my basic nutrient line (Micro, Grow, and Bloom) and in my opinion, Advanced Nutrients could have bumped up the phosphorus in the bloom bottle. I bought some NPK Raw phosphorus to supplement so I hope it corrects my issue. Thanks for all the info Lex B. I learn so much from you bro.



  23. DJ @RCANGEL on June 14, 2022 at 11:20 am

    Thank you bro, your videos are awesome



  24. Francisco Toledo on June 14, 2022 at 11:20 am

    you’re the best, I’ve seen lots of channels, lots of videos, I follow many people in IG, but you, my friend, are the one who shares clear and accurate info the most



  25. maziyar ameri on June 14, 2022 at 11:20 am

    Why the leaf is shining but other planet like matt



  26. Yunus Tegally on June 14, 2022 at 11:22 am

    How do you treat these deficiencies when your water run off is through the roof? Flush with plain water or flush with low nutes?



  27. pabuffa Buffa on June 14, 2022 at 11:22 am

    Awesome video!



  28. Doug Money on June 14, 2022 at 11:22 am

    This the best channel on here just gotta turn the speed up to 1.25x



  29. Miguel Mendes on June 14, 2022 at 11:24 am

    Is it possible for mobile deficiencys to start at the top of the plant ?



  30. shadow 08 on June 14, 2022 at 11:24 am

    Thanks for adding in that tid bit about night temps being a bit low can show up as the same symptoms. bc I was swearing up an down I for some reason had phosphorus deficiency in veg, even knowing it’s pretty rare but all signs said I did. Took me a few threads, other videos before seeing this one to figure out I was letting my room drop to low at night smh lol. Anyways appreciate the info. Not to mention ya save me alot of time an wasted effort man. Lol ✌🤙



  31. 1 1 on June 14, 2022 at 11:25 am

    Interesting so whats too low of a temp for vegetative growth?



  32. Bud Henry on June 14, 2022 at 11:25 am

    The best part is those leafs are not phosphorus deficient.



  33. b on June 14, 2022 at 11:25 am

    Do the red stems disappear when you start feeding phosphorus?And if they do,how long does it take from the moment you add the right amount of it?



  34. Jonny Wanny on June 14, 2022 at 11:26 am

    I am in veg stage atm, and it is looking like phosphorous…. but I’m thinking it could be mainly caused by the fungus nats…. they got bad for a little while, but then I got some insecticide soap, which has been working decently… atleast there aren’t as many flying around, but they are still in the soil alot…. the leaves are turning into a pale yellow, and then getting really distinguished spots, like black almost looking like freckles.

    Growth has slowed tremendously and a few places I topped the plant, it dried up the sap and nothing grew out of where I cut it…. although I am still noticing new growth, but the leaves are all smaller and it doesn’t seem to be growing much vertically anymore.

    The affected leaves are mainly older leaves, but even some newer leaves are showing signs, but not nearly as much… also the edges of the leaves are fraying and drying up as well.

    Not sure if my explanation was good enough, but I will also try to post a few pics. Hopefully we can get it figured out before I have to throw them all out… I’ve already thrown out a few younger plants that got too infected.



  35. Bradley k on June 14, 2022 at 11:27 am

    I’ve got tiny yellow spots on leaves, any suggestion I don’t really think it’s leaf sephoria



  36. Tom Hack on June 14, 2022 at 11:28 am

    Thanks



  37. M B on June 14, 2022 at 11:29 am

    thx for sharing knowledge!



  38. jansel perez martinez on June 14, 2022 at 11:29 am

    Yooooooo your explanations are just perfection 🤯



  39. David Hess on June 14, 2022 at 11:30 am

    Wow, Phosphorus was not what I was thinking but this is video s pretty much describing my plants issues. I thoght it was a Nitrogen toxicity just as you said but the rusting, browning/purpling on stems, etc are spot on. Will update once remedied…Thank you!!



  40. Jeremy Jk on June 14, 2022 at 11:30 am

    Hi friend still active? I’d like your help with diagnosing :/



  41. Jason Ivy on June 14, 2022 at 11:35 am

    Lex , what would cause something that looks like that but deformed only half the leaf on 30 % of leafs and looks mobile



  42. mobboss420 on June 14, 2022 at 11:38 am

    I know I’m a little late to the party but thanks for that I appreciate it



  43. the realist samurai on June 14, 2022 at 11:40 am

    there will be no drugs in 200 years & the universe will completely run out of all chemical elements & all chemical compounds needed to make and manufacture drugs Look up phosphate deficent cannabis it does not look good We will not be able to manufacture make & create drugs without chemical elements & chemical compounds that are needed to make create and manufacture drugs also the most needed elements required for manufacturing drugs are phosphate potassium and sulfur and all of those are expected to run out completely in 200 years so in 200 years there will not be any drugs because we need sulfur phosphate and potassium to manufacture grow create and make all drugs all drugs are made by chemicals and when chemicals run out so will all of the drugs. Cannabis will not survive the upcoming phosphorus crisis!!!



  44. daniel gonzalez on June 14, 2022 at 11:40 am

    & it’s that simple………., says the smart man 🤯



  45. Tario The Truck driver on June 14, 2022 at 11:41 am

    4 years old but new to me great video



  46. M city M city on June 14, 2022 at 11:42 am

    Thanks !



  47. LSD DayDream on June 14, 2022 at 11:46 am

    5 years later your still helping lex thank you



  48. RideForLifeCR250R on June 14, 2022 at 11:47 am

    I’m 3 weeks into veg in promix and have fed very little nutrient containing P to them and the dark leaves and dark almost mold looking spots appeared recently ( passed 48hr ).. is what has me believing I have a P deficiency.



  49. Josh Irvin on June 14, 2022 at 11:49 am

    Man Lex your awesome!!! I have this same thing going on with one of my plants right now that’s about halfway through its flowering cycle and didnt know why some of my leaves were starting to show these exact signs! Everything makes sense as to what shes been fed up until this point and points directly to a phosphorous deficiency! So I’m going to hit her with some fox farm Tigerbloom which is a 2-8-4 and should hopefully take care of the problem! 👍🙏! Fingers crossed!! Thanks alot for dropping some knowledge on this topic as it was exactly what I needed right now!!! Happy growing man!!✌



  50. Amknox on June 14, 2022 at 11:51 am

    thats why im subscribed .