Are you 18 or older?

You must verify that you are 18 years or older
to enter this website, by agreeing to the terms and conditions

What Are Cannabis Macronutrients and Micronutrients?

important cannabis nutrients

Cannabis plants need several micronutrients and macronutrients to grow, but among them all, a couple stands out due to being essential for them to develop correctly. These essential nutrients are divided into two categories: Macronutrients and Micronutrients. Macronutrients are Nitrogen (N), Phosphorus (P), and Potassium (K), and the main micronutrients are Calcium (Ca), Magnesium (Mg), Manganese (Mn), Molybdenum (M), Sulphur (S), and Zinc (Zn).

What Are Cannabis Macronutrients and Micronutrients?

As mentioned, cannabis macronutrients and micronutrients are essential for plant growth. Macronutrients are the foundation of plant health. They usually appear on the front label of cannabis fertilizers as N-P-K and are associated with a number indicating the concentration of each nutrient.


Nitrogen, phosphorus, and potassium are the primary nutrients your plants need to grow and stay healthy, resist diseases, and develop big flowers.

Nitrogen (N)

(N) is the most important macronutrient for the vegetative stage. Cannabis plants need a lot of nitrogen during growth and need way less during flower.

Cannabis Macronutrients N-P-K

Phosphorus (P)

Phosphorus helps in bud development and is vital for photosynthesis, producing energy, and transferring energy. This macronutrient is found in every cell in the cannabis plant and helps deliver nutrients to where they’re needed. 

Potassium (K)

Potassium plays a major role in root development, stress resistance, and overall plant growth while helping in a metabolic process called transpiration.


Apart from Macronutrients, cannabis plants need micronutrients, and they are just as important as the macronutrients for plant health, despite not being needed in high concentrations.

Boron (B)

Boron is essential in the branch and stem development. If your plants don’t get enough Boron, the cells become weak and, in extreme cases, can result in plant death.

Calcium (Ca)

Cannabis plants use calcium to strengthen green matter and regulate enzyme activity. This means that a calcium deficiency can affect enzyme regulation, causing stunted growth.

Iron (Fe)

Iron contributes to glucose production and plays a major role in the pigments in your cannabis plant.

Copper (Cu)

Copper is a micronutrient that helps in a metabolic process called photosynthesis. A copper deficiency usually leads to slow metabolism and an overall lack of energy.

Magnesium (Mg)

Magnesium is probably the most important micronutrient because it helps cannabis plants absorb sunlight for photosynthesis, playing a huge role in plant growth and flower development.

Manganese (Mn)

Manganese assists in nitrogen absorption and plays a minor role in plant reproduction, pollen production, and germination.

Molybdenum (M)

Molybdenum is vital for synthesizing certain enzymes that help break down nutrients, facilitating their absorption through the roots. 

Sulphur (S)

Sulfur helps produce the enzymes mentioned above, which are vital for plant growth.

Zinc (Zn)

Zinc also helps with enzyme production but also helps create several proteins that are vital for plant growth.

All of the macronutrients and micronutrients you just read are needed from seed to harvest, but their concentrations vary depending on the stage of plant growth.

Nutrients For The Vegetative Stage

Cannabis plants in the vegetative stage need more nitrogen and less phosphorus and potassium because, at this stage, they’re not developing buds. The ideal NPK ratio for this stage is 3-2-1.

cannabis macronutrients and micronutrients for different grow stages
Nutrients for different growth stages.

Cannabis Nutrients For The Flowering Stage

The nutrient requirements change when your plants start developing buds. During the flowering stage, you want to feed an NPK ratio of 1-3-2 and then change it to 0-3-3 during the last weeks of flowering. In this stage, your plants need less nitrogen and more phosphorus and potassium during the flowering stage because they have started developing the buds and no longer produce much foliage.

Now, it doesn’t matter what fertilizer you’re using. They all contain nitrogen, phosphorus, and potassium and at least a couple of the micronutrients mentioned, but it doesn’t mean they’re all the same. There’s one main difference: Organic vs. Synthetic (Inorganic).

Organic vs Synthetic Cannabis Nutrients

Every grower has its own style of growing. Synthetic growers swear synthetic fertilizers are better, and the same happens with organic growers. The truth is, there isn’t the best way of growing. You can grow excellent plants with both of them, but there are some differences in their use.

Organic Nutrients

Organic nutrients usually work best in soil and coco. The main difference between these nutrients is that organic nutrients aren’t water-soluble, meaning that your plant can’t absorb them and require beneficial microorganisms to break down the nutrients, so when growing organically, keeping these beneficial microorganisms healthy is vital.


  • Slow Release of Cannabis Nutrients

Microorganisms need to break down the nutrients before your plant can absorb them, making it harder to overfeed.

  • Improved Soil Structure

Organic growing depends on maintaining the soil healthy, and this process also improves soil structure, promoting water and nutrient retention.

  • Easy To Make

You can buy organic nutrients in most grow shops, but luckily, organic nutrients come from natural sources, so with a bit of research, you can make your own organic nutrients at home.


  • Takes Time

Growing organically requires patience because you need to wait at least a week or two for the microorganisms to reproduce and break down nutrients.

  • Requires effort

As mentioned, organic growing requires the microorganisms to break down the nutrients, so apart from keeping your plant healthy, you need to keep the substrate healthy for the microorganisms to survive.

  • Can Be Expensive

Organic nutrients are usually more expensive because of how they’re made, but there are several methods to make them yourself, such as composting and KNF.

Types of cannabis nutrients
Organic vs. Chemical nutrients

Synthetic Cannabis Nutrients

Synthetic nutrients are the best option for hydroponic growers because they are 100% water-soluble, meaning they’re provided in a form that plants can absorb immediately. On the other hand, it’s relatively easy to use too much and burn your plants due to being absorbed immediately.


  • Cheaper

Most growers use synthetic fertilizers because they’re usually easier to find, and they’re relatively cheap.

  • Faster Results

Synthetic nutrients are absorbed almost immediately, unlike organic nutrients. This makes them ideal for fixing nutrient deficiency fast and makes it easier to overfeed and cause a nutrient burn.

  • Easy To Use

All synthetic fertilizers come with the NPK ratio, making them easy to use, especially if you follow a feeding schedule.


Higher Risk of Nutrient Burn

Most growers use synthetic fertilizers because they’re usually easier to find, and they’re relatively cheap. Due to being readily available (unlike organic nutrients) it´s much easier to burn your plants, especially if you´re a beginner.

Nutrient lock

Synthetic nutrients are salts and they can build up over time, which can end up causing nutrient lock if you don´t flush the substrate.

Lots of Different Products

Almost all synthetic fertilizers come in three parts (such as Grow, Bloom, and Micro) but you may need several more additives so it can be hard to know exactly what to use if you´re a beginner.

Knowing the pros and cons of organic and synthetic nutrients helps you decide what’s best for your specific grow setup. Remember that the best nutrients are the ones that allow you to grow your plants to their maximum potential. It’s highly recommended you experiment with both of them before settling for one or the other!

Final Thoughts

Both micro and macronutrients are essential for the life cycle of cannabis plants, so remember to keep your plants well-fed and healthy. Keep in mind that when talking about cannabis nutrients, more isn’t better, so always pay attention to how your plants react and adjust the nutrient solution accordingly.

No Replies on

What Are Cannabis Macronutrients and Micronutrients?

Leave a Reply

10% OFF
Subscribe now to our email list and get 10% discount coupon code. Don't miss out!
join our family
I agree with the term and condition