Best Organic Nutrients for Growing Marijuana

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You don’t have to think about it too hard to realize that raising young marijuana plants isn’t all that different than raising children. As a cultivator (or new parent), you want your young-uns to grow up healthy. 

And you want them to be productive. Throughout their lives, you’re going to give them plenty of nurturing and encouragement, but it all starts with providing a healthful, well-rounded diet that includes all the important nutrients they need.

As a new parent, however, you may not be sure what’s best. The following is provided for helpful guidance.

5 Best Weed Organic Nutrients in 2021

Advanced Nutrients 5450-14 Voodoo Juice Fertilizer, 1 Liter

Voodoo Juice is a proprietary blend of eight microbial super strains that promote the development of larger root systems on seedlings, transplants, and clones. With better branching and greater root density and mass, users can expect significantly higher-producing weed crops. 

The product is effective in both soil and soilless systems and is available in a range of sizes from .25 to 23 liters.

Pros: Voodoo Juice enables plants to take in nutrients more efficiently. It’s a time and money saver.

Cons: The product tends to go moldy. It’s also pricier than other organic nutrient products.

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SUPERthrive VI30155 Plant Vitamin Solution, 1 Pint, Multi

SUPERthrive is an excellent, non-toxic vitamin solution for all growing systems, including soil, hydroponics, foliar spraying, and hydroseeding. A soil replenisher helps plants develop a strong root base and also helps to reduce plant shock in seedlings.

Pros: A highly-concentrated product with no expiration date.

Cons: It can be messy to use.

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Golden Tree: All-In-One Concentrated Organic Additive

Golden Tree All-In-One utilizes an original blend of amino acids, carbs, kelp, and minerals to encourage photosynthesis and improve the quality and quantity of yields. This product can be used in soil, aeroponics, hydroponics, and coco coir systems.

Pros: As an all-in-one solution, it is a good product for beginners that produces large, healthy buds. It improves yields by up to 20 percent. It’s also available in a wide range of sizes.

Cons: The product has an unfortunate pungent scent.

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Advanced Nutrients 2320-14 Bud Candy Fertilizer

The carbs and nutrients in sweet-smelling Bud Candy will give your plants a real energy high resulting in greater growth and yield. It will also help your seedlings and transplants have more than a fighting chance.

Available in a range of sizes from .25 to 23 liters.

Pros: Bud Candy provides a mix of important micronutrients your plants need, and it can be used in both soil and hydroponic systems. It can also be used right up until plants are harvested.

Cons: It is a fertilizer additive and should not be categorized as a true fertilizer.

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General Hydroponics Flora Grow, Bloom, Micro Combo Fertilizer set, 1 Quart (Pack of 3)

This three-part regimen of products contains a complete set of nutrients to help growers obtain bigger and better quality yields. It enhances flavor, aroma, and essential oils, and can be used for both hydroponic as well as soil-cultivated plants.

Pros: Available in multiple quantities. The ability to mix nutrients allows the grower to customize feedings. Helps in the development of roots, flowers, and fruit. Fun Fact: This pH-balanced product was used by NASA.

Cons: A little more expensive than one-part products. Stick with the larger sizes as the smaller bottles are less economical.

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Buying guide

What are organic nutrients?

These are nutrients that are derived organically from living sources such as vegetable and animal waste as well as sediments like rock dust and gypsum. For the most part renewable and sustainable, they have a positive effect on microorganisms in the soil, and because these nutrients remain in the soil, they tend to reduce nutrient runoff and waste.

Essential Nutrients for Plants

Just like humans, weed plants need a wide variety of nutrients to help in various phases of their development. Arguably, the most important is the trio of nutrients known as NPK, which stands for nitrogen, phosphorous, and potassium. 

(Fun Fact: The reason potassium is represented by the letter K in the periodic table is because it stands for Kalium, the medieval Latin term for potash.) 

Why is potassium important? Potassium encourages flowering and helps keep spider mites and other pests at bay. 

Phosphorous, on the other hand, helps with photosynthesis and resin production. If your plants suffer from a nutrient deficiency, more often than not, a lack of nitrogen is the main culprit.

Pile of Potassium Permanganate

The NPK trio isn’t the only collection of nutrients your plants need to thrive. Iron is needed for the production of chlorophyll and good overall health.

Magnesium assists plants in making the sugars they need to produce flowers, while calcium helps move those sugars along with nitrogen throughout your plants. Sulfur is a necessary nutrient for developing terpenes and potent oils. 

There are also several important micronutrients such as copper, manganese, molybdenum, and zinc.

Signs and Symptoms that your Plants Need Nutrients

Evaluate the pH of the Soil

In simplest terms, pH is the measure of how acidic or basic a substance is. Measured on a scale of 0 to 14, a substance that measures 7 is neutral.

A measure less than 7 is more acidic, while a measure above 7 is more basic. 

Weed grows best in slightly acidic soils, those that register a 5.8 to 6.8 pH, while plants grown hydroponically prefer a bit more acidity at 5.5 to 6.5 pH. Balanced soils are an important element in your plants’ overall good health, so keeping an eye on this is essential. 

While you’re at it, be sure to keep your other eye on the pH of the water you feed your plants. Your water pH should be between 6 or 7 on the scale.

Poor and Stunted Growth

Weak, stunted growth is often a sign that your plants are suffering from nutrient lockout. Nutrient lockout prevents plants from pulling the nutrients they need from the soil. 

This is commonly the result of pH levels in the soil, water, or nutrient solution being too high or too low.

Cannabis hemp male plant flower development

Non-organic, chemical fertilizers are typically salt-based and can cause this problem. To prevent nutrient lockout, it’s best to either use organic nutrients or, at minimum, avoid chemical fertilizers that are salt-based.

Yellowing and Wilting of Leaves

Don’t you feel proud when you have a plant that stands up tall, its leaves a vibrant healthy green? (Atta girl!) Sturdy plants with healthy green leaves and generous, resinous buds are a good sign you raised them right.

 Early signs of a deficiency, however, don’t have to mean your plants won’t succeed. It’s all a matter of staying aware and making the necessary adjustments.

Your plants’ leaves can communicate a host of nutrient deficiencies. For example, a lack of nitrogen will often result in a yellowing of older leaves at a plant’s base and eventually the entire plant. 

Left unaddressed, the leaves can get brown spots, then curl and drop off. Likewise, a deficiency of phosphorous will typically lead to yellowing and later purpling of the leaves. 

And as iron is needed for chlorophyll production, a deficiency of this nutrient will also show itself in a yellowing between leaf veins. If leaves start turning a pale green and then yellow, this may be an indication of a sulfur deficiency.

Frequently Asked Questions

What is the Best Cannabis Feeding Schedule?

The best feeding schedule to follow will depend on the fertilizer you use, and most products will come with a feeding chart that follows a 12 to 13-week growth cycle. The chart should include the nutrients you need to feed your plants, the ratio of feed to water, and in some cases a PPM (parts per million) range for the solution.

Investing in a PPM meter will help ensure your plants are getting the correct measure of nutrients and will help avoid nutrient burn. The nutrients your plants should receive will vary during the different stages of growth.

For example, your seedlings will not require any feed for the first three or four days until they have developed a few leaves and are officially entering the vegetative stage.

Male Hand Inspecting Cannabis Plant

In that early vegetative stage, they’ll require more nitrogen. However, once they enter the flowering stage, plants will need less nitrogen but more potassium.

In the final weeks leading up to harvest, you’ll want to begin to cut back on nutrients and at least a week prior to harvesting flush the plants with pH-neutral water. This will help your plants consume what is left of the nutrients they have stored leaving you with a smooth-tasting end product.

What Weed Nutrients Should You Buy?

Weed nutrients can be separated into either organics or synthetics and each have their advantages and disadvantages:


Pros: A common refrain of soil-based organic growers is that they produce more fragrant and smooth-tasting buds. This is likely because organic growers put a greater focus on nourishing the soil, which translates to more nourishing crops. 

Another positive attribute of using organic nutrients is that they are more slowly released resulting in a lesser likelihood of overfeeding and nutrient burn.

Cons: Organic nutrients often take longer to be absorbed by plants and they don’t protect as well against pests and harmful fungi and algae. Organic nutrients also cost more than synthetics.


Pros: In this world of instant gratification, synthetic nutrients provide instant availability to plants.

They are scientifically formulated to provide exact ratios of needed nutrients. They are also a more economical buy.

Cons: The instant availability of nutrients can be a risky business for newbie growers as overfeeding can occur resulting in nutrient burn. 

Additionally, synthetic nutrients are often salt-based, which, over time, will degrade the soil.

What Other Factors (Like Watering & pH) Should Be Considered When Growing Weed?

As noted earlier, the pH of your water and soil is crucial for your plants to be able to absorb the vital nutrients they need. However, too much or too little watering can also reduce the size and quality of your harvest. 

Roots need to be able to draw in nutrients to carry up the plant, but they also need room to breathe, and overwatering can end up drowning them causing nutrient lockout. If your plants are suffering from nutrient lockout, you can help reverse the problem by flushing them.

Marijuana plant close-up, medical marijuana

This uses pH-balanced water to help disintegrate salt and make a clear path for nutrients to be absorbed. After flushing, allow the soil to dry before slowly reintroducing fertilizer. This will also help avoid root rot.

Wouldn’t a third eye be really handy when growing weed? While keeping a close eye on pH levels and another close eye on potential nutrient deficiencies are both important, you could use a third to watch out for other factors like pests and disease.

For example, leaf septoria is a common disease that causes leaves to scab and yellow. This, too, is often the result of a nitrogen deficiency. 

If your plants are showing signs of leaf septoria, you should remove the afflicted leaves immediately. You may also need to completely replace the soil.


Just like raising children, there’s no right way to cultivate marijuana plants that results in the perfect adult every time. 

Parents need eyes in the back of their heads, and growers need at least a third eye to be sure to watch everything. 

As a beginner, you’re going to have to go through some trial and error. With a little effort and luck, however, your plants will be better off for it. Just remember, it’s all a part of the journey.