Canadians know better than anyone that there are a lot of factors involved in a successful grow op. The Government of Canada has been allowing its citizens to grow medical marijuana through the ACMPR since 2001. Now, it’s even legal to grow 4 recreation plants with no license at all thanks to the Cannabis Act.
According to Canadian growers, there’s way more to a grow op’s success than just the type of lights you use or sticking to a healthy watering cycle. Another critical element is making sure that your plants are getting the proper nutrients, but unfortunately, this is way more difficult than it sounds.
Reputable weed-growing sources are all saying the same thing – that one of the easiest ways to maximize yields is to focus on nutrients. But which nutrients should you be focusing on? And how can you make sure that your plants are actually getting the nutrients they need to thrive?
First, Focus on the Macronutrients
Like all types of plants, cannabis requires a high level of macronutrients to stay healthy. Some of these macronutrients are provided by the air, like oxygen, hydrogen, and carbon, so you don’t have to worry about adding these in, but some are provided by the soil.
In an indoor grow op, this means that it’s up to the grower to add these nutrients into the watering cycle so that the plants can uptake the nutrients they need from the soil (or whatever grow medium you’re using). The most important macronutrients are nitrogen (N), phosphorous (P), and potassium (K).
You’ll often see the letters N-P-K splattered across the labels of cannabis nutrient products. That’s because these are the most essential nutrients for getting the best yields. Not only that, but these nutrients are also essential for plant survival. Pages like this go into far greater detail about the nutrients and fertilizers needed to grow healthy cannabis plants.
Nitrogen deficiency is one of the biggest problems any grower can face. Nitrogen is a crucial nutrient since it allows plants to effectively complete photosynthesis, and we all know that photosynthesis is an essential process for plant survival.
If your plants are nitrogen deficient, you’ll start noticing yellow, wilty leaves near the bottom and pale, lime-colored leaves near the top. Too much nitrogen and the plants will start turning abnormally dark green. Just the right amount and you’ll be looking at vibrant, green plants.
Phosphorous is another essential macronutrient that cannabis plants can’t live without. It’s especially important for early-stage development, including things like root growth, stem strength, disease resistance, flower formation, and the ability to uptake nutrients.
With a phosphorous deficiency, your plants won’t have the immunity to withstand disease, and the leaves will start to change colors. But they won’t start yellowing as they would with a nitrogen deficiency. Instead, you’ll notice purple and brown spots forming on the lower leaves. As the deficiency becomes more severe, these spots will appear on all the leaves.
Unfortunately, your plants can’t just chow down on a few bananas to get their daily dose of potassium. It’s up to you to give it to them, and it’s crucial that you do because it helps to stimulate early growth and development and fend off disease.
When plants are potassium deficient, their leaves will almost appear to be burned or singed. This makes it extremely difficult to differentiate from plant burn from overheated lights and potassium deficiency. But as long as you’re keeping your lights a safe distance from the canopy, there’s a good chance that the problem has to do with a lack of potassium.
Next, Focus on Secondary Nutrients
Now you know that the main nutrients required for healthy plants and high yields are N, P, and K, but the nutrient work is far from over. Once you’ve got your macronutrients squared away, the next step is to focus on providing your plants with the necessary secondary nutrients.
There are 3 main secondary nutrients that are considered essential: magnesium (Mg), calcium (Ca), and sulfur (S). Magnesium is crucial for chlorophyll development, calcium is needed for nutrient transport and absorption, and sulfur is necessary for plant metabolism.
Don’t Forget About Essential Micronutrients
Once again, the work is not yet over. After macronutrients and secondary nutrients come micronutrients. Although micronutrients aren’t as crucial to plant development as N-P-K and Mg-Ca-S, they are definitely a necessary addition if you want maximum yields with your next harvest.
Here are the main micronutrients that you need to focus on:
The best cannabis nutrient products will contain all of these in trace amounts, so as long as you invest in quality nutrients, you shouldn’t have to worry about these too much.
A Quick Note on the Importance of pH
Even if you’ve got your nutrient dosage spot-on, it won’t matter if your plants are experiencing pH problems. If plant pH is too high or too low, your crop will have trouble taking in the nutrients that you’re providing. For optimal nutrient uptake, you’ll want to aim for a pH between 6 and 7.