Potassium DeficiencyFebruary 20, 2019
Potassium is the “k” in your N/P/K Ratio. Like Nitrogen and Phosphorus, it is known as a “Macro nutrient”, and is one of the three main elements needed in plant growth.
Potassium helps the pores of the plant open and close, which essentially, allows it to sweat and breathe. It is also responsible for the production of many enzymes the plant needs to grow. With out it, the plant would not be able to produce the starches needed for photosynthesis.
Because potassium is a major element in the movement of nutrition around your plant, if your plant is lacking in potassium, it will not digest food properly.
The Effects of Potassium Deficiency.
Without the right amount of potassium, the movement of nutrients around your plants is slowed down. In extreme cases, it will no be able to move nutrients around your plant at all, and your plant will starve to death.
The growth of your cannabis plant will be slowed down, and leave will grow smaller than usual. Being able to notice a potassium deficiency is very important to keeping a happy, healthy cannabis plant.
What Potassium Deficiency Looks like
With the lack of mobility of nutrients, you plant will become weak. The stems will be brittle and easily snappable if bent. The plant will try and eat the nutrients within itself. leaving dead patches on the leaves. The leaves will also be pale, and yellow, because of the lack of chlorophyll moving around the plant.
If the plants have begun to flower, the flowers will form later than usual, and grow smaller. This is all down to the lack of nutrients being moved around the plant.
How to Fix Potassium Deficiency
It will depend on what medium you’re growing in, but these problems are easily fixable! With any deficiency, it can be one of two things, either, a; your medium does not have enough potassium in it that is available to your plant. Or b; the PH of your medium if off, and needs restoring so K is within the correct range.
Potassium Deficiency in Coco & Hydro
Increasing the EC of your feed is a good way to add the extra food to your medium. Bloom nutrients, are high in K, and will be an easy way to fix the problem.
Increasing the EC of your feed by 0.2 points, every few days, will bring the correct level back to the plant. Be careful not to go too high. Gradual increases are important, and you must read the plant and the EC of your feed and run off. As soon as it looks healthy again, stop increasing the EC.
A PH imbalance can always be the cause of any nutrient problem! So make sure your PH is set to 5.8-6.2 in any hydro or soil less medium grows. Find out how to check you PH properly here:
Potassium Deficiency in Soils
If you’re using salt based nutrients in your soil, then increasing your EC for a couple of feeds should fix the deficiency within a week. If you’re growing organically, there are many things you can add to the medium, to increase the phosphorus content.
Organic Nutrients Sources
One more thing!
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