Vegetative stage occurs after the seedling stage, which can last 2 – 6 weeks.
During the growth period the plants most need nitrogen and potassium. If your plants become deficient in either of these during the grow period they will turn yellow.
The bigger your plant gets the more nutrients you will have to give it, as a general rule, the amount of phosphorous should be around half of nitrogen, while potassium levels can vary from one-third to half of nitrogen. Also you will notice that if you continue to give the same concentration of nutrients to your plants, at a certain point they will start to develop yellow leaves. The plant is trying to make it absolutely clear that she needs more food. The dose (strength) of your feed water needs to be raised or nutrients should be given more frequently.
When growing cannabis, it is always better to be cautious than overzealous. A plant growing with just a little added nutrition will develop better yields than a plant growing in over-fertilized soil.
Learn how to spot a nutrient deficiency
I’ve compiled a handy table below which lists the Essential nutrients that you really can’t miss out and the Supplementary nutrients that, although they aren’t always needed, are a great addition if you can afford it.
CANNA | Coco Coir | Vegetative Stage Nutrients
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