One of the most common deficiencies that you may encounter while growing cannabis is nitrogen deficiency. If gone uncorrected, nitrogen deficiency could significantly harm your plant.
In this article you are going to learn how to spot nitrogen deficiency in your cannabis plant - or any plant for that matter. Nitrogen deficiency is by far one of the most common deficiencies (if not the most common) that growers deal with. First, let's talk timing. Approximately 95% of the time nitrogen deficiency happens while the plant is in the vegetative stage. The vegetation stage is when cannabis plant need nitrogen the most. Now that you know when you are likely to see it, the first step in knowing what nitrogen deficiency looks like is understanding that there is two kinds of nutrients in your plant - mobile and immobile. Deficiencies that have to do with immobile nutrients tend to happen all over the plant at once. You start seeing the sickness all over the plant or the deficiencies can start at the top of the plant. Mobile nutrient deficiency (which includes nitrogen) starts at the bottom of the plant and slowly progresses up to the top of the plant.
At first, you will see the bottom leaves start to yellow between the veins while the veins stay green. This is known as interveinal chlorosis. Then, the veins start to turn completely yellow and then those yellow leaves drop off. While that's happening, the leaves above them start showing the same early symptoms. If you look under the leaves that have nitrogen deficiency, you will notice that the stems and the veins start to develop a reddish-purple color on the underside. Another symptom is a rapid reduction in growth. That happens both in terms of the height that the plant is gaining and the amount of foliage it's adding.
So how do you correct nitrogen deficiency? Easy, just add more nitrogen using a fertilizer or a solution sold in a Hydroponic store. Here are the top 3 nitrogen fertilizers:
Natures Nectar Nitrogen Fertilizer
Urea 46-0-0 Fertilizer
The recovery won't be instant, however, over the course of the next few days you will see the yellowing slow down and the growth resume. Unfortunately, there is no way to save the leaves that have already been damaged. Therefore, you can either let them fall off or cut them off. There you have it! You now know how to spot nitrogen deficiency and how to correct it.
NEXT: Magnesium Deficiency in Cannabis Plants
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