Cannabis Nutrients 101: What You Need to Know

Cannabis Nutrients 101: What You Need to Know

You've chosen your growing medium and where you want to plant your cannabis. But let's talk about nutrients. Nutrients are just as critical as your medium or the setting you choose to plant your clones or seeds. They're responsible for providing food to your plants so they can grow healthy and produce more yields.

When talking about nutrients for cannabis, you're going to encounter many things, such as percentages, types of nutrients, supplements, among others. Let's take a look at the things that matter.



Types of Nutrients

Cannabis needs different kinds of nutrients for it to grow healthy and yield quality buds during harvest. Each nutrient has a crucial contribution to the growth of your cannabis, making them non-negotiable. And during each phase of development, these nutrients have to be at a certain level for better optimization.


Cannabis Nutrients NPK

The three essential nutrients needed in cannabis growth are Nitrogen, Phosphorus, and Potassium. These three nutrients are used in high concentrations, with actual levels varying during the stage of development.

As a rule of thumb, you need a high concentration of Nitrogen and lower levels of Phosphorus and Potassium during vegetation, higher levels of Phosphorus and Potassium, and low levels of Nitrogen during flowering.



Nitrogen (N) is one of the essential nutrients needed during the early stages of plant growth.

If you notice, nutrients designed for the vegetative stage of growth have higher concentrations of Nitrogen, precisely to aid the development of cannabis.

Nitrogen is crucial for chlorophyll, which is essential to convert sunlight into energy and push its growth. You also need Nitrogen as part of the amino acids to develop protein, which makes your cannabis plants stronger.

Nitrogen also allows a plant to control its use of energy, being part of ATP. It's also essential to develop nucleic acid, which is critical in letting plant cells grow and multiply.



Phosphorus (P) is another essential nutrient needed by cannabis. While it's primarily for bud development, Phosphorus is also used during the vegetative stage, although in lower qualities.

When used in the vegetative stage, Phosphorus allows for a rigid growth of your plant, as it develops as a seedling. It helps the cannabis plant absorb nutrients so that it can grow stronger roots and healthier leaves.

You'll know that Phosphorus is low when you see a purple hue in the leaves.



Potassium (K) regulates water and salt content in plants by controlling the opening of the stomata or the pores of leaves, which are responsible for absorbing CO2, oxygen, and water.

It also activates the production of ATP, which stores energy from photosynthesis and develops glucose. The glucose formed is used as plant energy during growth.

Potassium deficiencies are evident when plants are weak and appear burnt due to the inability to regulate CO2, water, and oxygen exchanges.



Cannabis also needs micronutrients, which are in lower concentrations than Nitrogen, Phosphorus, and Potassium. But don't let the micro-tag fool you. While you need lower amounts, they still play a vital role in developing your cannabis plants.


Cannabis Micronutrients

To start, Calcium is a micro-nutrient that ensures the rigidness of cell walls in your plant. It helps plants grow and develop and ensure vital functions work as they should. When Calcium is low, the leaves curl, and you'll see brown spots on your plant.

Magnesium, meanwhile, serves as the core molecule in chlorophyll that's responsible for developing glucose during photosynthesis. It also helps metabolize glucose for plant growth. Without it, your plants cannot convert energy from sunlight.

Iron helps in pigmentation and leaf respiration. It's also a crucial nutrient in enzyme production.

While found in the soil, copper is crucial in developing plastocyanin. That is essential in triggering photosynthesis through electron transfers. While copper deficiency is uncommon, it is dangerous to your plants due to its role in photosynthesis.

Cannabis also needs air and water, as these are sources of Carbon, Hydrogen, and Water. With all things considered, let's take a look at the form of Nutrients.



Nutrient Forms: Liquid vs Powder


Liquid vs Powder Cannabis Nutrients


Cannabis nutrients come in two forms: liquid and powder. Liquid nutrients are often used indoors, while some are also capable of outdoor usage. It's a standard solution for a variety of growing mediums, including soil and hydroponics. Due to its state, growers may use liquid nutrients with drip lines, misting apparatuses, and hoses for efficient application.

The advantage of liquid nutrients is the ability to be absorbed faster. But, don't overdo it, as the fast absorption may be destructive when too much is applied. Liquid nutrients are used with a separate water tank for mixing. Each nutrient formula you buy has an ideal ratio per gram or teaspoon to the gallon. It's always best to follow the recommended proportions to avoid overfeeding.

Using liquid nutrients also entails having a watering schedule. That means knowing how much water you need, the kind and number of nutrients you apply, and how often you water your plants.

To be clear, you don't have to add nutrients all the time when you water. It's recommended that you stagger the application every other two waterings, depending on soil and plant health.

When starting, try going for a lower dosage while maintaining the ratios. Especially with seedlings, you need to see how the plants react to the nutrients you use. If they're not working as desired, try using another kind of nutrient formula.

Just as important is checking the pH level of your water before mixing your nutrients. As a rule of thumb, cannabis grows best at pH levels of 6 – 7 and 5.5 – 6.5 for hydroponics. Anything outside this parameter means your plants won't be able to absorb the nutrients it needs.



What About Organic Fertilizers?

As we all know, organic fertilizers are often sourced from animal or vegetable waste and may include sediments that have essential minerals. These work best for outdoor growing and are often in powder form.

Organic nutrients have less quick-dissolving nutrients and more elements that are good for soil organisms. You can get them at local nurseries and mixed with the soil. A good mix with the soil means only watering the plants, as everything is in the soil.

The best nutrients to get for an organic formula include blood or fish meal for Nitrogen, Bone meal or bat guano for Phosphorus, wood ash or kelp meal for Potassium, and Dolomite lime for Calcium and magnesium.

To make your life easier, you can buy soil mixes that have these nutrients. While beneficial, organic nutrients also have flaws. First, your plant needs more time to absorb it, potentially damaging your plants if not absorbed fast. They also need microorganisms to break nutrients, which isn't ideal in cold climates. And they can also attract insects and pests.



Nutrients vs. Supplements

Nutrients and supplements are two different solutions, but both contribute to the growth of cannabis. Nutrients are non-negotiable and must be applied to your plants. Supplements serve as a support system to exponentially improve plant quality.

To know if a formula is a supplement or nutrient, anything with low concentrations of NPK is a supplement. While supplements have low concentrations of essential nutrients, remember that too much of it can still cause your plants not to absorb these nutrients.

If you want to use supplements, it's best to use one made from the same manufacturer as your nutrients. These are likely to be blended with the right amount to avoid overfeeding.



Mixing Nutrients

If you buy off-the-shelf nutrients for your cannabis, the good thing about them is that they are already blended to the proper levels. That means vegetative nutrients will have the optimal blend of Nitrogen, Phosphorus, and Potassium.

But suppose you plan to mix things yourself, such as the organic nutrients; as a guide, vegetative nutrients have high levels of Nitrogen, low levels of Phosphorus, and moderate levels of Potassium. For the flowering stage, you can start with low nitrogen levels and high amounts of Phosphorus and Potassium.

One might ask, is it okay to mix different brands? And the answer is yes, but there are some risks involved.

First of all, mixing different nutrient brands may result in the non-absorption of nutrients. The measurements of each nutrient might not be the same with the two brands.

Second, the different nutrient formulas used by a brand are often tailored to fit with each other. You can easily add them without worrying about nutrient lockouts, provided that you follow the instructions on the packaging.



Flushing Nutrients

Flushing ensures the quality of your buds during harvest by ridding them of excess nutrients that accumulate in the plant and soil. That is done by ending all nutrients schedules and shifting to just plain water for your plants over a given period, depending on the growing medium. While it may sound basic, there are a lot of things to consider.

First, the water to be used must be at the proper pH levels, based on the growing medium. Second, there's a suitable time for it, as doing it earlier will affect your plant's yields.

Often, flushing happens two weeks before harvest, but this depends on the growing medium. Soil growers need around a week or two to thoroughly flush the plant of nutrients, while hydroponic growers need a few days. It's important to note that flushing also reduces green colors, which is normal. But you have to start harvesting when the sugar leaves start turning yellow. To know if your plants are ready to harvest after flushing, they should look lighter than before. Remember that your plants start to deteriorate after this, so better act quickly.



Putting It All Together

You shouldn't feel overwhelmed with the nutrients available in the market today, considering all the pre-made formulas made available off the shelf. But if you want to be adventurous and try other things, this article should serve as your guide to know what works and how each element contributes to a plant's growth.

That said, if you want no-frills usage, go for the pre-made ones to avoid complicating things. Keep in mind that different strains have unique reactions to the nutrients in the market, as some need slightly lower levels of Nitrogen or Phosphorus.