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Essential Plant Nutrients

Discussion in 'Marijuana Growing Guides' started by Vitamin 420, Apr 16, 2009.

  1. #1 Vitamin 420, Apr 16, 2009
    Last edited by a moderator: Mar 9, 2011
    In order to grow the biggest buds possible, we first need to understand how plants work and how they grow. This involves what are known as the "essential" nutrients - and I know a lot of people are aware of them, but understanding their function and role in maintaining plant health is something that is frequently overlooked. A number of growth problems can be avoided with the proper balance of nutrients. I see a lot of people using nutrients and trace elements without knowing what to expect, so let's go through this really quickly:

    Nitrogen: Nitrogen is essential for proper leaf growth and color, the synthesis of amino acids, proteins, nucleic acids, and also chlorophyll. Many proteins that rely on adequate nitrogen levels are the very ones that stimulate plant growth. With the proper levels of nitrogen, your plants should have a healthy green look to them, and unhindered growth. The older leaves will show signs of nitrogen deficiencies first, so if you notice any pale yellowing at the tips of your plants, it might not be a bad idea to up the nitrogen level slightly. As with all of these nutrients, keep in mind that any adjustments you feel you have to make should be in small quantities, and most importantly, gradual.

    Phosphorus: Phosphorus is a main component of DNA/RNA synthesis, as well as the development of roots, stems, and most importantly: flowers and seeds. The flowering period is where you want to begin adjusting phosphorus levels (if you so wish to) to suit the needs of the plant - some have seen increased quality and quantity of buds; but furthermore, a generally healthy level of phosphorus throughout it's life also yields strong plants with long roots and healthy growth levels. Because it is responsible for energy exchange (via ATP/ADP), phosphorus is essential to bigger plants, bigger yields, better buds - and better genetics. Deficiency symptoms include weak stems, stunted growth of leaves/roots, and other general poor growth characteristics.

    Potassium: Potassium is responsible for the synthesis of proteins and carbohydrates, as well as the development of roots, stems, and flowers. Through the exchange of potassium ions, the stomata of a plant are able to open and close - allowing carbon dioxide to enter the plant so it may be utilized for photosynthesis. Furthermore, it helps plants resist droughts, extreme temperatures, diseases, and also helps balance the pH level by neutralizing organic anions found in the plant. However, perhaps the most important function that potassium has is to distribute sugars throughout the plant in the form of ATP. Having healthy levels of potassium will be noticeable throughout the plant; everything from healthy roots to fat buds, and the little things in between, like the rate at which photosynthesis can occur at. So if your plants aren't looking quite as healthy as they should be; if they're not reaching for the sky quite as vigorously as they could, or if your leaves are starting to turn yellow/"burn" at the edges, you may have a potassium imbalance.

    Okay, let's break here and talk about the three as a whole: Nitrogen, Phosphorus, and Potassium. N-P-K. Many soils will have composition ratios listed on the front of the bag, and there's so many to choose from, so how do you know what works best for you? Well, I can't say there's an answer that's set in stone, because every plant and strain are diverse so their needs must be tailored to. There isn't a simple solution, given how complex life is, but here are a couple of suggestions:

    For rooting/germination, try to get higher levels of phosphorus, with less N/K, because at this point in the plant's life it wants to focus on cellular reproduction and growth of roots. Plus without much chlorophyll for photosynthesis, the plant needs to rely on adenosine triphosphate (ATP) energy to carry out vital functions. Roots also respire, which means a plentiful supply of oxygen will allow the roots to breathe easier, and better growth rates can be achieved. During vegetative growth, more nitrogen can be assimilated because the plant's growth is limited to the amount of nutrients, water, and sunlight it receives. They will otherwise grow incessantly. During flowering, an increase of phosphorus, once again, will ensure good genetic transcription and maximized production of flowers.

    Before we move onto the micronutrients, there are two other things we must examine: mobile vs immobile elements. Symptoms of deficiencies, based on the element, may either appear on younger leaves or older leaves, depending on if they are mobile or not. Boron and calcium are examples of immobile elements, since they cannot be returned to the plant through the phloem after they have been used. Therefore, younger leaves will show signs of deficiencies before the older ones to. On the other hand, mobile elements such as nitrogen, phosphorus, potassium, sulfur, and magnesium will be transported to younger leaves first, so the older leaves will show signs of a deficiency first. Secondly, and quite briefly, it is important to note that soil pH is also very important in governing the absorption rates of a majority, if not all, of the nutrients. With too much of an imbalance, certain nutrients might be locked out as others are absorped in higher quantities by the plant, which could in turn cause burning and unstable growth. The first and foremost way to ensure a happy plant is to feed it the right water.

    Now let's get onto some of the secondary nutrients - often referred to as micronutrients or trace nutrients.

    Magnesium: Magnesium is known for it's role in synthesizing chlorophyll and helping activate some enzymes which are responsible for rapid growth. There are hundreds of enzymes that are activated with magnesium and you may find that deficiencies include thin stems and weak, pale leaves. It's recommended to having epsom salts around in case you need to correct the balance (magnesium sulfate will do just fine)

    Calcium: Cell growth and division, cell wall structure, cellular transportation, and enzyme activation all fall within the range of Calcium's influence. Plants grow fast, firm, and upright with the proper balance of calcium - otherwise, you may notice brown, curling leaves, and stunted growth.

    Sulfur: Sulfur is an essential plant food that helps with the production of acetyl-CoA, and is therefore helpful for energy production, enzyme/protein formation, chlorophyll formation, and to a certain extent, increased root and flower production. It is also an important factor of the chromophore; a light-detecting portion of a phytochrome, so during the flowering period, the size of your buds can be affected by a healthy dosage of Sulfur.

    Chlorine: Chlorine is involved in the osmotic transfer of water across the stomata, and it aids in photosynthesis. A single touch on any part of the plant will provide enough chlorine for it, so don't worry about supplementation.

    Zinc and Boron: Both aid in the production of sugars/carbohydrates, and are helpful in production of flowers/fruits.

    Manganese: Manganese is an example of a nutrient whose rate of absorption is based on soil pH, It helps activate certain enzymes that are essential to chlorophyll formation, so deficiency symptoms may include chlorosis between the veins on the leaves and a lack of growth capabilities.

    Molybdenum: Molybdenum helps plants fixate Nitrogen into a bio-available form, but chances are your soils are already going to have this as a part of the mixture.


    Common Deficiency Symptoms: The diagnosis may be the hardest part of determining exactly which elements are lacking in your plant; for the reason that a lot of symptoms of element deficiencies manifest themselves into physical characteristics that are extremely similar to other element deficiencies. Some of the more common ones are chlorosis, where chlorophyll production becomes hindered and the leaves will consequently turn yellow and brittle. Deficiencies of nitrogen and phosphorus may cause the accumulation of anthocyanin pigments, and thus turning leaves very dark, and sometimes adding purple hues. Potassium and manganese will both cause necrosis, or patches of dead tissue in the plant. However, one notable difference is that a manganese deficiency will cause leaf tissue between veins to die, and a potassium deficiency will kill the tips first.

    Pictures of Deficiencies





















    Phew, there we go. Please keep in mind - this is meant to be a reference not a guide to nutrition of your plants. Balancing these elements is crucial, otherwise, you may find that too much of one will limit the plant's intake ability of another, so you may start seeing something like a calcium deficiency with too much magnesium. With even a single nutrient missing you may experience hardships in how your plant grows, so it's important to pay attention to how the plant looks and feels. Learning to read your plant's symptoms will help tremendously in fixing the problems that every grower eventually experiences.

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  2. good info.........
  3. Thanks. Nobody else found this useful? :confused:
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  4. Good info, thanks for posting it. Its kind of ironic though, you say that nitrogen deficiency is the most common plant problem in the world, but it seems that nitrogen overload or burn has gotta be the second most common problem there is. I guess its a fine line we walk.....;)
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  5. Yeah a lot of people have too much or not enough :p It seems as if some growers are bent on nuking their plants with nutes to get that enhanced growth, but like you said, there's a fine line to walk on. It's all about sensing what the plant needs.
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  6. I vote this to be a sticky. Great info vitamin. Hopefully I can apply and utilize this info. +rep
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  7. This. :hello:
  8. Hey thanks guys :) I'll throw this to the mods for a vote on the sticky, maybe I'll go through and add some information about the micronutrients for plants later tonight. It's hard to snap some pics to showcase examples of each deficiency because it's all correlated and the symptoms may be the same, you know?
  9. When i discover the problem for my plants, you are certainly welcome to utilize my pictures.:D
  10. Thanks man, that'd be a huge help! I'm sure people would be interested in seeing what the symptoms of various deficiencies look like. If you so happen to have one feel free to send me a PM with the link to it, and I'll include it up top.

    Also, there's some new info up there. I'll be going through and doing the rest of the micronutrients soon!
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  11. How is calcium both a mobile and immobile element?
  12. Oops, I didn't notice I put calcium down as both. It's an immobile element; thanks for pointing that out, it's fixed now ;)
  13. Thank you very much very very useful you help me understand my friends better
  14. Nice thread Doc.
  15. It must only move when it feels like it hahaha jk
  16. SUPER informative, I was wondering about this YESTERDAY, and badda boom here it is! Thanks for the info +rep
  17. very informative, thanks. but I think you left a couple out... hold on and let me re-go over it.
  18. damn good job man +rep for sure. you really know what youre talking about man or are extremely good at bullshitting. ha but i will definitely be bookmarking this for my first grow this summer.just what i was looking for. sticky:hello:
  19. Could you tell me where to get a good bloom fertilizer.And what type for lowryder2.
  20. Try a seaweed extract or fish emulsion, I just did a quick search on google and that seems to work for some people.

    The possibilities are limitless; the key things you want to focus on are not what brand/what type; rather, you want to focus on the composition of the nutrients.

    So look for more P, with less N

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