Going crazy with issues..

Discussion in 'Growing Marijuana Indoors' started by SoloG97, Aug 31, 2017.

  1. So maybe this is overwatering... it's seems that every time i water it with just water only and leave out everything including calmag the next day i get these spots all over... I'm starting to think I need to feed these nutes every time. But I don't want the nute taste when i harvest...

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  2. What medium are you using?
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  3. Fox farms ocean forest... and about 30 percent perlite...

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  4. Cal-Mag is easily depleted in soil, especially in flower. The first picture, the brown spots, look like a Cal-Mag deficiency.

    As for your nutrients, when you're in flower stage and soil, the plant has already used much of the nutrients available in the soil so you do you need to supplement nutrients when watering.

    Check your pH too, should be about 6.0-6.5 in soil.

    I wouldn't be too concerned about nutrient taste since you will be flushing the plant with plain pH water two weeks prior to harvest. This process helps to reduce all of the nutrients in the plant.

    In addition, just before harvest, leave your plant in the dark for 2 to 3 days to help reduce the chlorophyll in the plant.

    Good luck.

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  5. Wait - is it Calcium or Magnesium that is easily depleted in soil?

    If the soil you're using is that poor in nutrients why not add some kelp for Mg? If it's Ca, some lime? For that matter why not Dolomite Lime for both Ca & Mg? The possibilities to add nutrients to soil and then never worry about them again are endless.

    I don't understand - and with all due respect, please, why folks use the term "Cal-Mag" so often when these are two completely and very different elements - especially in soil...

    I've never bought a bottle of that stuff in my life and never will.

    Again - all due respect for everyone's methods.

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  6. Would u top dress the soil with it?? And one time and never worry about it again??

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  7. Would you recommend this brand, Jerry?

    Dolomite Lime - Granulated

    Link is to build a soil.
  8. I use it but have only really needed to while usimg led. Im going organic after my current rotation tho so ill bin it soon
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  9. #9 jerry111165, Sep 2, 2017
    Last edited: Sep 2, 2017
    For both Ca & Mg, Dolomite Lime is fine. For Ca only, Calcite Lime. For Mg only then kelp will provide what you need.

    Ideally you'd want to add them directly to the soil mix (around 1 cup lime per CF/7.5 gallons of soil) so that it is all throughout the soil but any of them can be worked into the surface with your fingers and then watered in well. Don't just leave it on the surface; work a good amount in as deeply as you feel you safely can without harming roots.
    And yes, this should be a one time thing. Because lime is a (crushed and powdered) rock, it's still a rock and can take a very long time to get broken down and used up - up to years. It can start acting in small amounts fairly quickly but can take up to several years before it's depleted. It requires microbial action alongside sulfuric and humic acids to break down. I'm not sure if you have any around but with anything you add to or topdress your soil with, adding some compost or worm castings can help speed things up because of the high levels of microbes (bacteria & fungus) contained in them.

    Then there's also the pH buffering capabilities of adding lime to your soil mix to consider...

  10. @Dickey's , sure, if you want to pay to ship rocks (albeit ground rock) - but I say to heck with paying for shipping. You can find Dolomite Lime at any Home Depot, Lowes or hardware store/garden center for $4.00 to $10.00 for a #25 to #50 pound bag.

    "What Is Dolomite Lime?
    Dolomitic lime is a rock. It can be quite pretty. It is calcium magnesium carbonate, CaMg(CO3)2. It has about 50% calcium carbonate and 40% magnesium carbonate, giving approximately 22% calcium and at least 11% magnesium."


  11. Jerry, I use a #5 pot so are you saying 1 cup per #5 pot of FFOF isn't too much?
  12. To the OP:
    How about a foliar of Epsom salt solution. Cant hurt. Pure MgSO4.What do you think Jerry
  13. I don't but have seen plenty of folks get fine results with it. There's no doubt it could work under the right circumstances.

  14. You're right jerry. I've never experienced a magnesium deficiency, however I have experienced a calcium deficiency. Adding Cal-Mag helped to solve that problem so I began using that term. However, you're absolutely right, calcium and magnesium are two different things.
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  15. The rule of thumb is usually around one cup per cubic foot of soil, which is roughly 7.5 gallons so I'd go between a half and 2/3 of a cup when mixed directly into the soil (5 gallons) and a little less if topdressing.

  16. It seems from what I've seen on the boards that a lot of folks use it (bottled cal/mag) in hydroponic and coco grows.

  17. Yes, it's used regularly to refer to calcium deficiency which is why I made a habit of combining the two. However, for the sake of new learners, I'm happy you noted that calcium and magnesium or two separate elements that the plant needs.
  18. I don't understand - and with all due respect, please, why folks use the term "Cal-Mag" so often when these are two completely and very different elements - especially in soil...
    Cal-Mag® 2-0-0

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