Guides | 07.25.2023

The Top 10 Best Marijuana Fertilizers On The Market

Get bigger, better, and tastier buds with the best weed fertilizers on the market.

A person’s diet plays a huge role in how healthy they will be throughout their lifetime. The same applies to your beloved cannabis. In order to grow the healthiest plants with bigger, more flavorful buds, they need the proper nutrients.

If you don’t know anything about cultivating cannabis, then attempting to get your babies on a good nutritious diet so that they grow up to be big and strong is a mind-boggling mission.

You will discover along the way that an overspill of nutrients can be a bad thing and that different stages of your grow have specific nutritional needs. Oh, and that chemical reactions can occur when nutrients aren’t mixed right — no big deal.

The Best Weed Fertilizers

Photography by Kaya Blaze Kelley for Herb

Finding the perfect fertilizer for cannabis comes with a lot of overthinking for sure. How could you not when there’s the risk of having the wrong blend of nutrients ruining your entire crop? But it doesn’t and shouldn’t have to be so stressful. With the right stuff, you’d be amazed how something that seems so complex could be so simple, and of course, rewarding.

When considering what type of fertilizer you’ll choose for your plants, you have primarily two choices: homemade or professional. Buying fertilizer made for cannabis or another professional fertilizer comes with fewer mistakes as they contain the required amount of nutrients for the herb to thrive. That also makes it easier on you.

You don’t have to worry about overmixing or undermixing, or causing any nasty chemical reactions. Whether you’re taking the hydroponics approach or sticking to good old-fashioned soil, we searched and selected a few of the best weed fertilizers for every grow. That way, you get the garden of fire you deserve:

Best Weed Soil Fertilizers

Photography by Kaya Blaze Kelley for Herb

If your precious pot plants are growing in soil, then you don’t need to feed them much more nutrients than they already have. The beauty of soil is that it comes pre-packed with the nourishment your plants need, including the three magical basics NPK (Nitrogen, Phosphorus, Potassium). Inevitably, however, cannabis will require additional feed, which is where the fertilizer comes into play.

Most seasoned growers will always recommend organic fertilizer over anything. That’s because it’s more forgiving and nutritional. Making your own using a combination of fish meal, blood meal, wood ash, etc., would be cheaper than going with a retail product, but again, retail products, most of which are still organic, contain the ideal mix of nutrients. They eliminate not only the guesswork but also most risks. Here are some of the best weed fertilizers for soil growing:

Essential Nutrients For Optimizing Cannabis Growth: An In-Depth Guide

Healthy cannabis growth depends on a balance of several essential nutrients, including macro and micronutrients. In this guide, we’ll delve deeper into what these nutrients are, why they’re important for your cannabis plants, and how you can ensure your plants get the right amounts for optimum growth and yield.

Understanding Macro and Micronutrients


The primary macronutrients cannabis plants require include Nitrogen (N), Phosphorus (P), and Potassium (K), often referred to as NPK. 

– Nitrogen (N): Nitrogen is crucial for plant growth and development. It plays a pivotal role in photosynthesis and the creation of proteins, amino acids, and enzymes. Nitrogen deficiency often results in yellow leaves. 

– Phosphorus (P): Phosphorus is vital for energy transfer and storage in plants. It is especially crucial during flowering and helps increase bud size. A phosphorus deficiency can lead to stunted growth and smaller yields.

– Potassium (K): Potassium regulates water and nutrient movement in plant cells and strengthens immunity against diseases. It’s also essential for protein synthesis and the quality of the buds. A lack of potassium can lead to weak stems and slow growth.

Secondary Nutrients and Micronutrients 

Apart from the primary nutrients, cannabis also needs secondary nutrients – Calcium (Ca), Magnesium (Mg), and Sulfur (S), along with micronutrients like Iron (Fe), Manganese (Mn), Boron (B), Molybdenum (Mo), Zinc (Zn), and Copper (Cu). While needed in lesser amounts, these elements are still crucial to the overall growth and development of the plant.

Fertilizers: Feeding Your Cannabis The Right Nutrients

Feeding your cannabis plants, the correct nutrients is a critical aspect of the growth process. The fertilizers you choose should cater to the specific needs of your cannabis strain and the stage of growth. 

– Vegetative Stage: During the vegetative stage, your cannabis plant requires high levels of Nitrogen and adequate amounts of Phosphorus and Potassium.

– Flowering Stage: As the plant moves into the flowering stage, it needs less Nitrogen and more Phosphorus and Potassium. Too much Nitrogen in the flowering stage can lead to reduced bud growth.

Moreover, when growing in mediums like coco coir, you might need to supplement with extra Cal-Mag to avoid deficiencies. Also, bear in mind that different strains of cannabis may have unique nutrient needs.

Monitoring And Adjusting Nutrient Levels

Proper monitoring and adjustment of nutrient levels are crucial in optimizing cannabis growth. Over-fertilization can lead to nutrient burn, while under-fertilization can lead to deficiencies. It’s essential to regularly check your plant’s leaves for signs of nutrient deficiency or toxicity and adjust your feeding schedule accordingly.

As a grower, understanding the nutrient needs of your cannabis plants can be the key to achieving a high-quality yield. Remember, healthy cannabis growth is a balance of several factors, and proper nutrition is one of them. Always ensure that your plants get the right nutrients in the correct amounts for optimum growth and yield. 

Natural Vs. Synthetic Fertilizers: Which Is Best For Your Cannabis?

The choice between natural and synthetic fertilizers for your cannabis garden is a critical one. Both types have their unique advantages and drawbacks, and the best choice often depends on your individual circumstances and growing goals.

In this guide, we will delve into the differences between natural and synthetic fertilizers, exploring their benefits and limitations to help you make an informed decision.

Benefits Of Natural Fertilizers

Natural fertilizers, often referred to as organic fertilizers, are derived from plant or animal matter, compost, or mineral deposits. These include items like worm castings, bat guano, fish meal, bone meal, and kelp meal.

– Nutrient Availability: Natural fertilizers release nutrients slowly, providing a steady nutrient supply over a longer period. This makes it less likely to cause nutrient burn.

– Improves Soil Health: Organic matter in natural fertilizers improves soil structure, promotes beneficial microbial life, and enhances water retention capabilities.

– Environmentally Friendly: Natural fertilizers are renewable, biodegradable, sustainable, and don’t contribute to environmental pollution.

Limitations of Natural Fertilizers

– Slower Nutrient Release: While a slow-release of nutrients is generally beneficial, it might not meet immediate nutrient deficiencies.

– Cost: Organic fertilizers can be more expensive than their synthetic counterparts, especially for larger grow operations.

Benefits Of Synthetic Fertilizers

Synthetic fertilizers are man-made inorganic compounds, usually derived from by-products of the petroleum industry. These include most water-soluble NPK (Nitrogen, Phosphorus, Potassium) fertilizers.

– Immediate Nutrient Availability: Synthetic fertilizers offer immediate nutrient availability, beneficial for addressing nutrient deficiencies quickly.

– Easy to Use: They are typically easier to apply and control nutrient ratios than natural fertilizers.

– Cost-Effective: Synthetic fertilizers are often less expensive than natural alternatives and are highly concentrated, offering a lot of use per unit.

Limitations Of Synthetic Fertilizers

– Risk of Over-Fertilization: Due to their high nutrient concentration, there’s a risk of nutrient burn or over-fertilization.

– Environmental Impact: Overuse of synthetic fertilizers can lead to nutrient runoff, potentially causing water pollution.

– Doesn’t Improve Soil Health: Synthetic fertilizers don’t improve the soil’s organic matter or foster beneficial microbial life.

Natural Vs. Synthetic: Making The Choice

Ultimately, the choice between natural and synthetic fertilizers depends on your specific circumstances. If you’re an organic grower, committed to sustainable practices and long-term soil health, natural fertilizers are the best choice. If you need to address nutrient deficiencies quickly, or if cost is a significant factor, synthetic fertilizers might be your go-to.

Remember, it’s also possible to use a combination of both. Some growers use natural fertilizers as their base and supplement with synthetic fertilizers when necessary. The goal is to provide your cannabis plants with a balanced, accessible nutrient profile to optimize growth and yield.

The choice of fertilizer should align with your cultivation practices, environmental consciousness, and the specific needs of your cannabis strains. Whichever option you choose, make sure you monitor your plants for signs of nutrient deficiencies or excesses and adjust your feeding strategy accordingly.

If you’re interested in learning more about the growing process, check out this article based on one of the leading growers in the cannabis world. We even have an in-depth guide for growing for any people that are just starting out in cannabis cultivation. 

Best Hydroponic Weed Fertilizers

Hydroponics is one of the most popular growing techniques today. For those new to the hydro way, plants grow with their roots planted in water rather than soil. This way, there are no loose soil bits to clog pumps or any other part of your hydroponic system. When going soilless, it is especially important to avoid overfeeding, which is easy to do with the wrong fertilizer. Otherwise, your plants will either get damaged or lose their life completely.

Shopping for hydro fertilizers is a breeze; much more straightforward than with soil fertilizers. That’s because most are designed for cannabis since that’s the method that the majority of growers, especially indoor cultivators, are using. With that being said, you can expect a balanced, healthy diet for your plants from the top-notch formulas.

However, there is a small downside, and it’s that you will have to end up buying most products separately, or together as a kit, as they divide up their nutrients to meet the specific needs of each growing stage, and avoid overfeeding all the while. Here are the best weed fertilizers for hydroponic growing:


Advanced Nutrients Big Bud

Produce larger, denser buds bursting with terps, aromatics, and potency with the Advanced Nutrients Big Bud Liquid Fertilizer. The larger the harvest weight, the bigger the value. Though the Big Bud fertilizer is not a fix and only an additive for the flowering stage, customers guarantee exceptional results when it comes to big buds and tight nugs.

It’s advertised as sufficient for both soil and hydro growing. However, it seems to be a preferred nutrient supplement for hydro over soil, as the soil, in conjunction with this feed, typically results in overfeeding and plant death. Follow the instructions carefully, and your plants won’t get burned, only more beautiful and tasty.



Advanced Nutrients Overdrive

specially formulated to raise their metabolism and increase nutrient intake with the help of occurring hormones and vitamins. Not only that but to also make roots and stems super strong, enabling plants to thrive and therefore be more resistant to disease. Some customers even claim it has brought their dead plants back to life. This formula encourages cannabis plants to develop gorgeous colors too, a plus for any grower that cherishes the beauty of their favorite herb.



General Hydroponics Flora Series

Nothing helps a cannabis plant to blossom and develop abundant yields in a hydroponic atmosphere like a product designed for that specific purpose, such as the General Hydroponics Flora Series. If your plants are struggling, then this kit has a solution for every growing stage. Supposedly, even NASA and Antarctic research scientists prefer Flora because of its reliability. In addition to providing primary, secondary, and micronutrients to enhance yields and crop quality, they improve flower flavor and aroma. Happy garden, happy grower.


Best Weed Coco Fertilizers

Growing cannabis in coco coir, aka coconut coir, is advantageous for marijuana and growers alike. It’s easy to learn to grow using coco coir, and coco coir is a rich source of oxygen and retains water like a champ. Moreover, it’s eco-friendly and reusable, and less vulnerable to pests and diseases.

Keep in mind, however, that coco coir is prone to calcium and magnesium deficiencies, so supplying your plants with extra supplements may be necessary. Thankfully, the supplies are friendly for most budgets. Here are the best weed fertilizers for a coco grow:

Canna Coco A + B & Cal-Mag

For keeping those magnesium and calcium levels up, all you need is the Canna Coco A NPK Formula plus the B formula, along with a bottle of Canna Cal-Mag. We recommend the Botanicare Cal-Mag Plus as it’s highly beneficial in both calcium and magnesium.

The Canna Coco A & B set is tailored for coco grows. The formulas are composed of high-value minerals, in addition to natural chelates and fulvic acids for optimal nutrient absorption. Customers claim that with this brand, they get lush green foliage and rock hard, dense nugs, aka that sticky icky. Just have a gander at the photos in the review section on Amazon and see the results for yourself.

Alternatively, you can use the Fox Farm Trio for hydroponics, which we just mentioned earlier. The kit works great at preventing calcium and magnesium deficiencies, and you don’t need to use a lot of it being that it’s strong. If you’re worried, then you can always pair some Cal-Mag with the bunch. Fox Farm provides a feeding schedule as well, so as long as you follow it correctly, then you should be good to grow.

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