What is NPK?

NPK represents nitrogen (N), phosphorus (P), and potassium (K). They are the most important nutrients when it comes to cannabis cultivation. They are considered the 3 macro nutrients essential to plant growth.


There are other essential macro and micro nutrients you will need in order to grow a strong and healthy plant!

Click HERE  to read about the 15 essential plant nutrients. 
You can read more about NPK here.


Deficiencies occur in your plants when they are not given enough nutrients, or they are given too much of one nutrient and it causes a nutrient lockout. 


NPK (Nitrogen, Phosphorus, Potassium) are the macro nutrients your plant needs to survive. An NPK deficiency can cause detrimental effects in your plants. 

Nitrogen Deficiency
nitrogen deficiency can cause loss of leaves and stunting of growth.



How to Detect:
Lower leaves will turn yellow and/or fall off. Your plant will be pale in color (light green). 
Cannabis plant showing Nitrogen Deficiency


Phosphorous Deficiency
A phosphorus deficiency can leave your plant vulnerable to pests and diseases.


How To Detect:
Leaves will be slow growing and become blue / green with brown spots. The stems might turn a purple color and the leaves will curl downwards. 
Cannabis plant showing Phosphorous Deficiency





Potassium Deficiency
A potassium deficiency can result in your plant being vulnerable to diseases.



How to Detect:
Older leaves will turn yellow or brown and the edges will appear as if there is nutrient burn. Both yellowing in the middle of the leaves and burnt looking edges is a sign of a potassium deficiency. 
Cannabis plant showing Potassium Deficiency


Our friends at GrowDoc App teamed up with Niagara College to study the effects of nitrogen, potassium, and phosphorus deficiencies on cannabis plants!


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Check out their article below or CLICK HERE
N P K Deficiency - THC, Terpenes & Yields


We have just received some incredible results from our new Niagara College report showing the complete effects of nitrogen, potassium, and phosphorus deficiencies! 

It’s understood that having a problem with your cannabis plant like a nutrient deficiency is detrimental to your plant, but do we know exactly how bad it can be? In this new study, we find out how N, P, and K deficiencies affect variables such as THC, terpenes, yield, height, and more!

The studies were completed with two different strains, Shishkaberry, and Cold Creek Kush. These were then stripped of either nitrogen, phosphorus, or potassium and then compared to a control plant. 

We began NPK deficiency studies with Niagara College in late May of 2021 with the goal of gaining information on the effects all three deficiencies have not only on the cannabis plant but the cannabis itself. With this new report coming back from the lab we can see exactly how each deficiency affects the amount of THC and cannabinoids.


Some of the standout results of this study were:


  • Up to 28% DECREASE in THC

  • Up to 25% DECREASE in Terpenes

  • Up to 96% DECREASE in Yield 

  • UP to 50% DECREASE in Height


With a control plant being the benchmark, we found decreases in THC levels as much as 28% in a plant experiencing phosphorus deficiency in the Cold Creek control. Total terpenes dropped as much as 25% in plants experiencing a nitrogen deficiency. This drop was more significant in the terpene, Beta-Myrcene, which dropped a whopping 45%! Total height dropped around 50% for pants experiencing any type of nutrient deficiency. The biggest drop in any measured value was in yield, with an incredible 96% decrease from the control plant. The control yielded 136 grams while an example of a deficient plant only yielded 5.6 grams. 

We will continue to conduct cannabis studies and share the results with all of you! Take a look below and check out the full free report PDF!

Link here

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