How to Make Organic Fertilizers to Grow Cannabis at Home?

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Added 30 November 2021

organic fertilizer

Growing cannabis at home is rewarding — there’s something special about having ample supply, not to mention the possibility of making concentrates, edibles, and everything else you desire right at home. 

Most cultivators choose inorganic nutrients — the usual liquid commercial fertilizers to grow big, fat buds. However, unless you’re a commercial cultivator obsessed with quantity rather than quality, growing organic cannabis is definitely a better choice for home-growers. 

Before you run to your nearest store to grab some organic ferts, let me remind you that making your own organic fertilizer is as easy as making your morning tea! 

How? Well, organic fertilizers don’t need too many ingredients, and you’d be surprised to know that you can make some of the best fertilizers with stuff lying in your kitchen cabinet. 

There are hundreds of recipes to make effective organic fertilizers all over the internet, but in this article, we will show you five easy recipes that are cheap and inexpensive to make. 

Understanding Fertilizers

Before we proceed with the recipes, let’s first understand how fertilizers help you grow cannabis plants.

What Does a Cannabis Plant Eat?


Without turning this article into a biology lecture, let’s understand what essential nutrients your cannabis plant needs.

Your cannabis plant needs seven macronutrients, out of which the primary macronutrients are nitrogen, phosphorus, and potassium — famously known as NPK. No prizes for guessing that N stands for nitrogen, P for phosphorus, and K for potassium. 

Other macronutrients include carbon, oxygen, hydrogen, calcium, sulfur, and magnesium. While the plant gets its fair share of carbon, oxygen, and hydrogen from the soil, water, and air, the cultivator will need to provide the remaining macronutrients. 

Here’s a quick look at what the primary macronutrients do and why they are essential:

  • Nitrogen is beneficial for photosynthesis, so it’s best used during the plant’s vegetative phase.
  • Phosphorous is essential to develop a healthy root system, so you need to use it for a young plant that’s still growing its roots. Phosphorus is also necessary during the stage between the plant’s vegetative and flowering stages. 
  • Potassium is good for the production of plant proteins that strengthen its immune system. Potassium also supports big fruits and flowers, so it’s necessary during the reproductive or flowering stage. 
  • Calcium is responsible for plant tissue production and also helps the plants grow healthier. In addition, it holds the cell walls together and activates specific enzymes necessary for the plant to grow better. 
  • Sulfur helps the plant produce chlorophyll during photosynthesis to produce essential vitamins, starches, oils, sugars, and many other components. 
  • Magnesium also plays a key role in photosynthesis by capturing the sun’s energy. It also manages important activities during photosynthesis. 


Then, the plant also needs micronutrients such as copper, iron, zinc, iodine, cobalt, manganese, selenium, and molybdenum. Although crops don’t need micronutrients in large amounts, they are important for the plant during various stages of growth, including respiration and photosynthesis. 

Plants absorb these macronutrients and micronutrients from the soil, but your soil may not always have enough for your cannabis plant. Cannabis is a hungry plant, after all. Thus, commercial fertilizers include a balanced combination of macro and micronutrients to encourage growth and reproduction. 

Why Use Organic Fertilizer?

Cannabis Nutrients

You can supplement the right base soil conditions to grow the cannabis plant in two ways: via organic and chemical fertilizers.

We recommend using organic fertilizers as they are more eco-friendly and harmless to the plant. The only condition is that you must use organic fertilizers comprising of all macro and micronutrients. Most organic soils contain generous amounts of these nutrients, but you may have to supplement them frequently if your plant shows any signs of deficiencies. 

One advantage of using organic fertilizers is that they are essentially free — you can prepare them with household items. And you get better control over the plant’s growth as you can dial in exactly what they require to harvest better-tasting buds.

Fertilizer Recipes

Alright, let’s cut to the chase — here are five super easy ways to make organic fertilizers to grow cannabis at home.

  • Coffee Grounds 

Coffee grounds

Ideal for the growth phase

Coffee grounds have been used across the globe for years as a natural fertilizer since it contains several essential nutrients, including magnesium, phosphorus, iron, potassium, calcium, and nitrogen. 

Since coffee is acidic, it encourages the development of acetic bacteria in the soil — a perfect environment for plants like cannabis, tomatoes, and even blueberries. Most cultivators use coffee grounds during the cannabis plant’s vegetative phase as it contains almost 2% nitrogen. 

Coffee is also known to absorb some heavy metals that are notorious for contaminating the soil. However, what makes coffee even more interesting is that it attracts beneficial earthworms that fertilize the soil. 

Although some growers sprinkle coffee tea (like compost tea) or diluted coffee at the roots of the plants, it works the same even if you just spread used coffee grounds down at the roots. 

To prepare coffee grounds fertilizer, add coffee grounds to your composting tank or mix it within the soil substrate, or you can dilute it in one liter of water and let it sit for 24 hours.

Make sure you maintain a proportion of 2 grams per liter of soil, or it will be too acidic. We recommend using a pH pen to keep acidity in check; the soil’s pH should be between 6 and 6.5.

  • Wood Ash

wood ash

Best for the final flowering stage

Ash makes for excellent mineral fertilizer. It’s rich in potassium and phosphorous, making it suitable for the final flowering stage.

For wood ash, you can collect the ash from any wood source. As long as it’s real wood, it will work. Wood ash also contains lots of calcium and a few other trace minerals. Therefore, it serves the plants well, especially when applied at the beginning of the flowering stage. 

If you manage to get fresh wood ash, simply collect it shortly after the wood has burned and store it in a dry place for some time. A handful of ash per pound of soil should work wonders. You can also substitute it with other phosphorus fertilizers. 

However, be careful not to go overboard. Using too much wood ash can make the soil very alkaline by raising the pH levels.

  • Banana Tea

banana peels

An ideal full-cycle flowering fertilizer

The banana fruit is one of the most potassium-rich natural products, and as mentioned above, potassium is key to the plant’s development. Plus, it has adequate phosphorus, too. It contains 45% potassium and 3.25% phosphorus.

Therefore, banana tea fertilizer helps the cannabis plant process carbohydrates, starches, and sugars, increasing its energy reserves for more vigorous leaves, stems, and buds. In fact, this fertilizer can help you grow 20% fatter buds.

Another reason banana tea is excellent is that it encourages the biosynthesis of terpene proteins in the cannabis plant.

To prepare banana tea fertilizers, start by adding 3 to 5 peels in a liter of water and add two tablespoons of honey, sugarcane, or molasses. Once the mixture is cool, remove the banana peels, mix the remaining water with two more liters of water, and shake well.

This fertilizer is best applied during the last six weeks of the flowering stage.

Or, you can collect a few banana peels, dry them in the sun, powder the dried peels in a coffee grinder, and spread them at the base of the plants, just like you’d use other products. Adding banana peels during the cannabis plant’s flowering stage will encourage the buds to fatten up and grow healthier. 

  • Eggshell


Excellent calcium deficiency correcting fertilizer

Eggshell fertilizer is an excellent calcium corrector as it offers a boost of calcium to your cannabis plant, along with other elements. Each 100 gm of eggshells contain the following ingredients:

  • 380mg calcium
  • 375mg magnesium
  • 99.3gm phosphorous
  • 41.5gm potassium
  • 0.5gm iron

To prepare a fertilizer that not only fixes calcium but also provides magnesium, you can add Epsom salts along with eggshells. 

To start, crush six eggshells in a mortar or grinder. Then, add them to two liters of water with 15 gm of Epson salt. Once the water starts boiling, keep stirring it for five minutes.

Then, cover the vessel with a cloth for 24 hours to let the eggshells release all the nutrients in the water. Filter the water the following day with a kitchen strainer and apply it directly to the soil.

Another technique to prepare an effective calcium fertilizer involves vinegar. Collect two dozen eggshells and dry them in sunlight. Roast the shells in medium heat on a pan until a few shells turn dark brown. 

Roasting the shells also adds phosphorus to your mix. Powder the shells using a coffee grinder. Next, add the powder and vinegar into a bowl in 1:3 proportions — add one cup of eggshell powder for every three cups of vinegar. 

The mixture starts bubbling immediately. Let it sit for a while until the bubbling subsides. Next, stir the mixture well and store it in a container with the lid open for a few hours. Finally, once the solution seems like it has settled down, you can close the lid and store it. However, wait for at least two weeks for the vinegar to dissolve the calcium before you can use it on the plants. 

To use this fertilizer for cannabis plants, mix one tablespoon solution with one liter of water and spray it on the leaves or water the roots. This fertilizer will also fix bloom end rot in tomatoes!

  • Brewer’s Yeast

The quintessential multi-purpose fertilizer

Brewer’s yeast — not to be confused with baker’s yeast — is an excellent food for us and our favorite plants! It is rich in amino acids, proteins, and minerals, making it an ideal multi-purpose fertilizer.

To prepare the brewer’s yeast fertilizer, simply add a small spoonful of yeast to a liter of water and stir well.    

That’s it. 

Then, spray the water over the soil until you see it drain at the bottom. Not only does Brewer’s yeast contain several nutrients, but it also fights against soil toxins, according to research. 

Summary: How to Make Organic Fertilizers to Grow Cannabis at Home?

Isn’t it easy to prepare your own organic fertilizer to grow cannabis at home?

So, what are you waiting for? See which fertilizer your plant needs and start preparing it now. And remember always to check the fertilizer and soil pH balance to prevent pH imbalances. 

Your plant will thank you with fat buds.


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Great informative. Thanks.