Yellowing in early early flower

Discussion in 'Growing Marijuana Indoors' started by cobud90, Jul 20, 2017.

  1. I just switched to flower and did 24 hours with the lights off to start it off. It's the next day and all of the newer growth has turned yellow.

    -Soil ph is about 7.5
    -I just used some bio thrive veg nutrients in the last watering.
    -I'm using 2x 300vipar leds that are about 12 inches from the canopy.
    - temps get to a high of about 78 and a low of 70.

    Does anyone have any ideas as to the reason for the Yellowing?

    Attached Files:

  2. Don't post pics taken under LEDs. Can't tell a thing about what the plant looks like. When you feed a plant, it takes around 3 days for any evidence to show up on the plant. If you gave nutrients that were too strong that far back, then you might have figured out the problem. Too early in flower for them to be shedding. That happens at the very end of the flower cycle, so something isn't right. The correct pH for your water and any feeds you mix up is 6.3 to 6.7. Watering out of pH range over a period of time will hamper the roots of the plant from being able to take in nutrition. Light burn doesn't appear as yellowing of leaves, but be aware that LEDs burn hotter to plants than other types of flower lighting. You need to make sure they're not too close. It depends on the quality light you're working with actually. I've never used the brand you have. My guess is you went to heavy on the nutrients. Nutrients are nothing more than plant food and most people think they do a whole lot more than they do. Of course, they're important to growing a healthy plant, but if you're using soil and use a good quality grow soil mix, the need for tons of nutes is reduced quite a bit. Plants don't need to be fed unless they are hungry. They usually show you that by an overall washing out in the color of the foliage to a more yellowish green. A plant that has had too much nitrogen will have very dark green leaves. The healthy plant is that nice rich blue/green we all know and love. You judge the health of the plant by the new growth too. Old growth represents time already gone by and it's the new growth that tells you what's up. But you would really help yourself out by taking the time to do the research and reading up on the plant and it's nutritional needs at different times in the life cycles. It needs different nutrients during veg than flower and if you want to use them to your benefit, take the time to really learn what you're doing, using and why. I would give straight pH'd water (tap water works best since we don't treat with chlorine here in the U.S. now....chloramine is used instead and it's not harmful to your plants). We've used it straight from the tap for years with no problems. Filtered waters are stripped of valuable micronutrients that the plants need and use and I've seen people get deficiencies from using different forms of filtered water. Hope this helps you some. TWW
  3. Is it possible that the 24 hours of darkness flip could have caused this? I went in this morning right after lights out and noticed that the plants are not nearly as yellow as they were when the lights went on yesterday.

    It looks like they new growth has started to green up now that it had the 12 hours of light.
  4. Do plants naturally get 24 hour dark periods before transitioning into flower? No, next time just switch times normally they will be fine.

    And no the dark cycle did not caused that. Your ph is probably too high for one of the NPK nutrients
  5. Your ph is too high for one. You should be feeding with 6.5 range.

    I've had quite a few plants do this. The funny thing is that they will yellow on top. It's nitrogen deficiency. Usually the lower leaves yellow first. I swear though during stretch when you first flip a plant it will yellow on top if you don't feed it enough. It may have a little to do with the more powerful bloom lighting.

    I raised the nitrogen component of my feed up about 2ml/gallon and the yellowing reverses or slows.

    People tend to think that in bloom a plant doesn't need as much nitrogen. I don't think this is true especially in the stretch at early flower. The plant actually needs more nitro then the rest of the grow at stretch to make all that extra tissue along with extra p&k. You can't just give the extra p&k and not add a little nitro for a vigorous growing plant or it will get yellow. Towards the end of flower I taper nitrogen lower again.

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