best marijuana fertilizer

Which Nutrients Are Best For Growing Cannabis?

Table of Contents

What’s the difference between nutrients?

If you’ve decided to start growing cannabis for the first time, trying to figure out the best nutrients for your setup can be very confusing. There are many nutrient companies, and each company creates multiple lines of nutrients and supplements for different purposes.

The abundance of cannabis nutrient options can be overwhelming

As a cannabis grower, your goal is to give your plants the right amount of nutrients at the right time. There are two main life stages for cannabis plants (vegetative stage and flowering stage). Each stage has different nutrient requirements. Luckily, many nutrient companies make great products even though they’re all using different formulas and techniques. Here’s how they differ:

  • Nutrient Ratios – Each brand has different nutrient ratios they believe are optimal for each stage of growth.
  • Ingredients – There are many different combinations of chemical and organic compounds that can add up to the same nutrient ratios. Each compound reacts differently with each other. This means you can see two nutrient bottles with the exact same NPK ratios on the bottle, but they will provide somewhat different levels of nutrients to your plants. The ingredients determine whether nutrients are considered organic or synthetic.
  • Designed for Soil or Hydro – It’s really important to match your growing medium with your nutrients. “Soil” nutrients are different from “Hydroponic” nutrients so make sure you’re getting the right kind! Coco coir is generally considered a type of hydroponics when it comes to nutrients, though there are also nutrients specifically designed for coco coir. Typically, hydroponic nutrients contain everything a plant needs to grow and can be used in any grow medium.

Important Tips on Cannabis Supplements

  • Don’t confuse supplements for nutrients. If the NPK ratios printed on the front of the bottle are really low (like 0.2-0.2-0.1) it means that this product is some type of supplement. Base nutrients provide all the necessary NPK and micronutrients for healthy growth, so supplements are not necessary for plants to thrive. Some supplements are helpful, but going overboard may cause unwanted reactions or burn your plant. Do you need supplements to grow great weed?
  • Use nutrients and supplements from the same company to minimize unexpected interactions. Combining nutrients and supplements from different companies greatly increases the chance of unhappy plants! It’s also a good idea to only add one new supplement at a time and watch how plants react before adding anything else new or different. If this is your first grow, try to pick just one or two supplements that appeal to you. It’s easy to go overboard. Nutrient companies will happily sell you supplements you don’t actually need.

Now that you understand the basics, are you ready to learn how to figure out the best marijuana nutrients for your setup?

Examples of Good Can nabis Nutrients

Here are several examples of trustworthy nutrient brands that work well for growing cannabis. These nutrients have been extensively tested by real marijuana growers and are known to produce great results!

  • General Hydroponics – Soil, Coco Coir & Hydroponics
  • Fox Farm – Soil & Coco Coir
  • Botanicare – Soil & Hydroponics
  • House & Garden – Soil, Coco Coir & Hydroponics (lately it’s been difficult to find certain H&G products online)
  • Canna Coco – Coco Coir
  • Dyna-Gro – Soil, Coco Coir & Hydroponics

Honorable Mentions – I haven’t tried these nutrient brands yet, but they are popular for growing cannabis

General Hydroponics Flora Trio

General Hydroponics offers a simple duo with one bottle for the vegetative stage, and one bottle for the flowering stage called FloraNova Grow + Bloom. This nutrient system is cheap, simple, and easy with excellent results in soil/coco/hydro. The biggest issue I have with the duo is the liquid is so thick it can be annoying to measure out.

However, their Flora trio is a winner. A tried and true favorite of mine, the Flora trio works very well for growing cannabis. I’ve had great success with it in every grow medium including soil, coco coir, and hydroponics. I used this nutrient system for almost a decade and have always been thrilled with the results. I’ve been testing new nutrient systems so I can report back to our readers like you, but based on my years of success I know you’ll be happy with the Flora trio. Best for…

  • Soil
  • Coco Coir
  • Hydroponics

·Soil or Coco Coir

Follow the instructions on the side of the bottle at half-strength for great results in soil or coco. It’s recommended to also use a Cal-Mag supplement if using filtered water, growing in coco, or using and LED grow light (all tend to increase the Cal-Mag needs of your plant). I prefer the GH version called CaliMagic, and use at 1 tsp/gallon.

·Hydroponics / DWC/ Bubbleponics

Use similarly to soil or coco, just make sure to also get Hydroguard to protect your hydroponic roots from root rot.

Check out a few different grow journals featuring the GH Flora trio

Fox Farm Nutrient Trio

The FF trio is a popular nutrient system for cannabis growers that contains a variety of natural sources for nutrients like earthworm castings and bat guano, which cannabis plants thrive on. Fox Farm nutrients contain too much organic matter for DWC/hydro (increasing the chance of root problems), but all that organic matter is great for plants in a hand-watered environment to enhance smell and flavor of your finished product. Best for…

  • Soil
  • Coco Coir

·Soil version

Very concentrated, less is more. “Grow Big” & “Tiger Bloom” provide most of the major nutrients your cannabis needs, while “Big Bloom” has many micronutrients and beneficial compounds that help nutrient uptake and root health. This trio works extremely well by itself, just follow the feeding schedule (here’s a PDF, here’s a JPG) from Fox Farms at half-strength to start.

Check out a grow journal using the FF trio for Soil!

·Coco version

Use the “hydro” version of Fox Farms nutrients when growing in coco coir. Two bottles are the same as the soil trio, but the “Grow Big” bottle is formulated slightly differently for a soilless grow. Follow the feeding schedule (here’s a PDF, here’s a JPG) from Fox Farms at half-strength to start. Generally, the Fox Farms nutrient system will prevent Cal-Mag deficiencies, but it’s good to have extra Cal-Mag on hand just in case whenever growing cannabis in coco coir, if using filtered water, or if growing with LED grow lights.


Botanicare is a great company that’s been around for as long as I’ve been growing, and whose supplements I’ve been using for years (specifically, their Hydroguard supplement is the most effective thing I’ve used to prevent root rot in a hydroponic setup). Best for…

  • Soil
  • Hydroponics

·Soil version (Organic)

Use “Grow” in the vegetative stage, and “Bloom” in the flowering stage. Organic. Claims to be usable in hydro, but I’ve only seen growers use it in soil so that’s what I’m recommending it for ?

·Hydroponic version

Get the trio: Grow, Bloom, Base (need all 3 bottles for all phases of growth)

The three bottles are all that’s needed to get your plants successfully to harvest time, just follow the feeding schedule from Botanicare [PDF], starting at half the recommended strength. Hydroguard is an important root supplement that will help prevent your plant from getting root rot in a hydroponic reservoir. The KIND series has been highly recommended by several hydro growers I know in real life and they make some very useful supplements.

From a grower: “Botanicare KIND is like the opposite spectrum [of the Botanicare Pure Blend series]. The Base is just Nitrogen and Calcium. Grow and Bloom both have most of the minerals in them, along with things like sea kelp. The Bloom is also 0-6-6. Grow at 2-2-4. So quite literally you can call the shots on Nitrogen and Calcium. That level of control hasn’t been around a great deal in our market. For the savvy grower, this is a pretty nice tool.”

House & Garden – Often difficult to find online!

The House & Garden lineup is an expensive but effective line-up. From a grower: “H&G was started by a top researcher from Canna. They are right outside of Amsterdam and because cannabis is legal there, so both Canna and H&G are able to do R&D using cannabis. I don’t know about Canna, but I know that House and Garden makes all their own nutrients in-house and they work great.”

The biggest downside of House and Garden (besides price) is it’s getting harder to find online. This brand is often best purchased in person at a hydro store. Get a custom nutrient schedule directly from the people at House & Garden via their free online nutrient calculator.

Name of base nutrients for…

  • Soil – Soil A + B
  • Coco Coir – Coco A + B
  • Hydroponics – Aqua Flakes A + B
  • Recommended supplements: Roots Excelurator, Algen Extract,Bud XL, and shooting powder

This plant was grown using the House & Garden Line-up (A+B as base nutrients, plus the supplements Roots Excelurator, Algen Extract, Bud XL, and shooting powder)

Canna Coco

Canna Coco is a very popular company for pot growers. Their nutrients have been specifically designed to grow cannabis in coco coir (as you may be able to tell from the name).

  • Best for Coco Coir

This combo is a crowd favorite – many coco coir growers write in to tell us this is their favorite cannabis nutrient for growing in coco coir. Get a custom nutrient schedule from Canna or use this pre-made one [JPG].

From a grower: “Canna is a Dutch company and one of the best IMO. They make a great product line for growing in coco coir and test their products on real cannabis plants.”

Another grower said, “Canna products are one of the only nutrient lines to be developed primarily for cannabis (and tested on live plants). They’ve been doing so for almost 30 years. Cost is a little higher than competitors but worth every penny.”

A different grower added, “Canna – I have only used their coco line, but it is the highest quality you will find.”


Originally designed for orchids, Dyna-Gro nutrients have proven to work exceptionally well for cannabis plants. If you want professional results without spending a ton of money or having to mix multiple bottles together, this combo give your plants everything they need from seed to harvest. Dyna-Gro nutrients are suitable for any growing medium including soil, coco, or hydro.

  • Best for Soil, Coco or Hydroponics

Dyna-Gro Grow + Bloom – Use “Grow” in the vegetative stage and “Bloom” in the flowering stage.

Dyna-Gro Grow + Bloom is my recommended nutrient system for newbies. One bottle for veg, one for bloom. Super simple!

One Last Tip…

When using a complete nutrient system like the ones listed above, always start at half the recommended strength by the manufacturer, and only increase nutrient levels if your plant is getting pale. If you’re giving too low levels of nutrients, the entire plant will start to appear overall pale or lime green. If you have a different nutrient deficiency (diagnose your plant here), chances are it’s caused by incorrect pH, not by too-low levels of nutrients.

It’s a good idea to always start at half the manufacturer’s recommendation ! Most nutrient companies recommend way too much for growing cannabis!

Why not keep adding more and more nutrients? Doesn’t more equal better? No, nutrients are more like a multivitamin than food. After your plant has enough nutrients, adding more gives you diminishing returns, and too much starts causing the following problems.

A cannabis plant turns pale all over (left) when it needs higher levels of nutrients overall. If plant is a healthy green (right), stick to half the recommended dose.

Too high levels of nutrients causes…

  • Nutrient burn – nutrient burn causes tips of leaves and edges of buds to appear burned. It isn’t a huge deal but doesn’t look as pretty, especially if it gets bad enough to spread to your buds.
  • Random nutrient deficiencies and lockout
  • Buds don’t grow as big as they could have in the flowering stage, especially if levels of Nitrogen are too high
  • Leaf discoloration may spread to the sugar leaves on the buds (not a big deal, but not pretty either)

Now that you understand everything you need to know about picking the right nutrient system, check out some supplements!

Learn About Cannabis Supplements:

What’s the Best NPK Ratio for Cannabis Nutrients?

For the best results, your cannabis needs the following nutrient ratios…

Where is this information? Most nutrient bottles display 3 numbers, often called N-P-K, which stands for Nitrogen, Phosphorus and Potassium

Why “K” for Potassium? The atomic symbol of Potassium is “K” from Neo-Latin kalium.

In other words, you want to use a “Vegetative” (high Nitrogen) or “general purpose” nutrient formula for the first stage of life known as the vegetative stage. If using high-quality soil, you can skip vegetative nutrients for the first 3-4 weeks while your plant uses up the nutrients in the soil, otherwise, you should start with vegetative nutrients around the time your plant opens its first leaves.

Use a “Bloom” (low Nitrogen) nutrient formula with plenty of P & K for the flowering stage. Start using bloom nutrients when buds start forming to make sure your plant gets plenty of Phosphorus & Potassium, which are crucial to bud development.

Phosphorus tends to increase the number of flowers, while Potassium helps increase the bulk/weight of flowers. Be careful, though because going overboard with either one can burn your plants!

The main thing is to avoid giving too much Nitrogen in the flowering stage, as it can discourage bud development and add an unpleasant taste to buds, which is why a general-purpose plant nutrient isn’t a good choice in the flowering stage.

In a pinch, nutrients for Shultz “cactus” or “succulents” can be used in the flowering stage until you get better nutrients because it contains low amounts of N and plenty of P & K.

Note: Don’t use any type of non-organic time-released nutrients (like fertilizer spikes, or “slow-release” Miracle-Gro soil) because they deliver too much N in the flowering stage and may reduce bud growth.

Cannabis needs plenty of P & K to make buds in the flowering stage!

The Best Cannabis Nutrients Aren’t Enough! Check the pH of your water to plants to prevent nutrient deficiencies

It may surprise you that the most common reason growers get nutrient deficiencies is because the pH is too high or too low. This happens even if the right amounts of nutrients are present because your weed simply cannot absorb the nutrients if the pH isn’t in the correct range.

Optimum cannabis pH for..

Soil: 6.0 – 7.0
Coco Coir: 5.5 – 6.5
Hydroponics: 5.5 – 6.5

Checking the pH will make a huge difference to your grow by keeping plants vibrant and healthy. It only takes a few minutes each time you water your plants! If you get a digital pH pen, it only takes seconds to test your pH!

Organic vs Chemical (Synthetic) Nutrients

This is a common question we get at Grow Weed Easy: Are organic nutrients better than chemical nutrients? It’s not a matter of which one is better, because they’re good at different things.

Organic Nutrients

  • Bud Smell & Taste – Many growers believe organically grown cannabis will create the most fragrant and “smoothest” buds. Some of the best benefits to smell and taste seem to come from using composted soil that’s been amended with nutrients from natural sources. This creates a living soil with colonies of beneficial microorganisms and is often associated with a bolder taste and smell in buds. However, watering your plants with liquid nutrients that just happen to be organic tends to get results similar to synthetic or mineral-based nutrients. It seems to be the soil that makes the difference when it comes to organic growing.
  • More Natural – Especially when growing in a living soil, you’re creating a home for your roots that is as close to nature as possible (only better because you’re making sure your plant gets everything it needs!)
  • Not for Hydroponics – Organic nutrients are not the best choice for hydroponic systems because any organic matter can cause unwanted stuff to grow in your reservoir. It’s possible to grow organic hydro but let me just say this: as of yet, I’ve never seen organic hydroponics go well for someone, though I wouldn’t mind being proven wrong ?

Recommended Organic Nutrients

There used to be a ton of organic soil nutrients in bottles (like the now-discontinued GO Box) but many options have disappeared as growers switch to using amended compost for their organic nutrient needs. Why? The organic nutrients in bottles get similar results to mineral nutrients. The biggest difference in organic growing seems to come from using actual compost and/or amended soil.

  • Nature’s Living Soil (super concentrated organic compost nutrient mix) – amend bottom 1/3 of your plant container with this special organic amendment, and plants will be able to slowly use the nutrients “on-demand”. Even if your plants are already growing in soil, you can sprinkle a little of this on top of your soil and water to deliver organic nutrients. Note: smells strongly of manure!
  • Dr. Earth Organic Nutrients – dry nutrients
    • Vegetative Stage: Homegrown Tomato, Vegetable & Herb Fertilizer (better) or All-Purpose Fertilizer (good)
    • Flowering Stage: Flower Girl Bud & Bloom Fertilizer
  • Roots Organics Terp Tea Fertilizer Set (Grow & Bloom) – This dry formula is mixed with aerated water and brewed for 24 hours to create a “tea” for your plants. Can also be used as a top dressing.

Best supplement ingredients for organic growing

  • Sea kelp – a source of K, helps plants resist heat and stress
  • Leonardite – full of humic acids for happy roots, resist stress
  • Protein hydrolysate (contained in many supplements) – helps plants produce big roots and be more resistant towards water stress
  • Potassium Sulfate (also called “Sulfate of Potash”) – the sulfur and potassium promote smells and bud development in the flowering stage

My favorite organic supplement contains all of the above: Floralicious Plus

How to Adjust pH in an Organic Soil Grow (regular PH Up and PH Down can harm the natural balance of the soil)

Organic cannabis growing is rewarding!

Chemical Nutrients (including synthetic and mineral-based nutrients)

  • Possibly Increased Potency – While organic nutrients may increase the smell and taste of buds, chemical nutrients tend to increase the potency.
  • Faster Growth and Bigger Yields – Synthetic nutrients provide nutrients to plants in the most easy-to-absorb forms possible. This results in somewhat faster growth and improved yields since the nutrients don’t need to be broken down in the soil by a colony of microorganisms before they become available to your plant.
  • Only Choice for Hydro – These are the best cannabis nutrients for hydroponic systems because they are less likely to cause stuff to grow in the water reservoir. However, chemical nutrients can also be a great choice for soil or coco because of the increased potency and faster growth!
  • Easier to Get Nutrient Burn – Although you can give cannabis plants nutrient burn with organic nutrients, it’s much easier to give them nutrient burn with chemical nutrients. This is due to the easily absorbable nature of these nutrients. Synthetic nutrients get taken up by your roots whether the plant needs them or not.

The General Hydroponics Flora trio is a synthetic nutrient that’s so effective it was used by NASA to grow plants in space!

Don’t want to use nutrients at all? Learn how to compost your own super soil (or buy super soil pre-made online)! Super soil compost contains all the nutrients your plant will need from seed to harvest so you just need to add water. As an added bonus, with composted super soil you rarely need to worry about maintaining your pH. Instead, the composting process develops a colony of microorganisms in your soil that will automatically take care of the pH for your plants to an extent (like in nature), while slowly providing nutrients on demand.

Super soil compost has been amended so no additional nutrients are needed. Just add water!

Can I create my own nutrient system?

Creating a nutrient system is more complicated than just adding “Nitrogen,” “Phosphorus” and “Potassium” plus all the various micro-nutrients in certain ratios. There several different chemical compounds that provide each of these nutrients and they’re not all equal.

What's the "best" cannabis nutrient system? There are literally thousands of choices! Learn what to look for and get examples of great marijuana nutrients.

The 15 Best Nutrients and Fertilizer for Growing Cannabis

The soil you use when growing cannabis might be the foundation of your plants, the soil you use only works as well as the fertilizer you’re using within it. The fertilizer and nutrients you use to nourish your plants are vital to the health of your plants and will directly affect your plant’s potency.

Fertilizing your plants with the right nutrients can help them flourish. Without the proper nutrients, you might spend a lot of time cultivating plants that end up not being as potent as you would have hoped. Luckily, we’ve done the hard work for you. In this article, we’ll break down the best nutrients and marijuana fertilizers for growing cannabis plants in 2020.

Last updated: February 18, 2020

Top 15 Best Nutrients and Fertilizers for Cannabis 2020

Sure, you can spend your time conducting experiments and researching the best fertilizers and nutrients for your specific cannabis seeds. But in the process of all of this testing, you will spend a lot of time and even more money trying to figure out what works. We’ve compiled all of the best information based on our own research and personal experience to curate this list of some of the best nutrients and fertilizer products on the market.

Depending on the strain you are trying to grow, and the make-up of your grow space, you can use this information to choose the product that’s right for you.

1. Fox Farm Liquid Nutrient Trio Soil Formula

Fox Farm is a well-known and well-respected brand in the growing community. They attract a lot of new growers who continue to use them well into their growing practice. The main reason that people continue to choose this brand is because of their low-price point, high-quality formula, and versatile line of products. They have hydroponic blends and use nutrients that cater to a lot of different strains. Using their products requires a low learning curve, so even the most inexperienced growers can grab a bag, read the instructions, and incorporate this fertilizer into their plants.

What We Liked
  • Hydroponic growing option available
  • Wide range of products
  • Great price point
  • Versatile to any strain
  • No experience necessary
  • Create healthy vegetation
  • Focus on producing big buds
What We Didn’t Like
  • They don’t make much distinction on how to use the nutrients throughout different stages
  • Requires a bit more research when dealing with longer flowering times
Final Thoughts

There’s not much we dislike about Fox Farm. The price is right, the advanced nutrients are stable, and the formulas are simple. If there was anything to nitpick at, it’s that many first-time growers don’t know when to switch from one stage to another.

We recommend speaking with other growers and watching your plants for specific signs that it’s time to move on to the next round of nutrients. You don’t want to risk missing out on the opportunity to nourish your plants.

2. General Hydroponics Organics Go Box

The General Organics Go Box is a go-to choice for a lot of first-time growers because the brand has decades of experience producing products that are specific to growing weed. It’s an all-in-one solution for growers who aren’t sure where to start when it comes to using particular nutrients in their growing process. It’s an organic mix of fertilizer and nutrients that comes with eight bottles of nutrients in each pack.

What We Liked
  • All-organic formulas
  • Safe to ingest
  • Excellent customer service
  • Quality guarantee and return policy
  • Works well for both hydroponic nutrients, soil fertilizer, and alternatives like coco fiber
  • Reasonable prices
What We Didn’t Like
  • Not all the formulas are OMRI certified.
  • Organic hydroponics has noted that the lack of certification on some of their products is due to the cost of certification
Final Thoughts

The Go Box is a top choice for growers regardless of experience. General Hydroponics continues to make great fertilizers and nutrients for weed plants. The development that went into these products is apparent.
Overall, we stand behind this product because if anything does go wrong, the company is easy to contact and has outstanding customer service.

3. General Hydroponics Flora Gro, Micro, Bloom Combo Fertilizer Set

This set is one of the original nutrient sets that was popularized by indoor cannabis growers back in the day. It’s a comprehensive three-part building block nutrient system for your weed plants. It is one of the most popular formulations, thanks to its unique ingredients and consistent performance.

The Flora Series contains three ingredients: FloraBloom (for flowering and/or fruiting), FloraMicro (growth & bloom), and FloraGro (for vegetative stage growth). This combination is made up of highly purified concentrates for supreme solubility. The pH of the elements is correctly balanced for superior formulation as well as reliability.

Different combinations of the Flora Series allow you to provide your plants with the appropriate nutrients concerning the growing environment and growth stage. This high-performance fertilizer will ensure that your weed receives the perfect balance of secondary, primary, and micronutrients.

What We Liked
  • High-performance three-part fertilizer for veg, flowering, and fruiting
  • Greatly purified concentrates are highly purified
  • Properly balanced pH levels for superior formulation and reliability
  • Suitable for all grow media
  • Stimulates structural as well as vegetative growth
  • A preferred choice for Antarctic and NASA research scientists
What We Didn’t Like
  • Bottles may have broken factory seals
  • Bottles are smaller for the price
Final Thoughts

This is a great fertilizer set that supports pretty much any stage of flowering. It’s easy to use, even for beginners, although we found the price to be higher than other sets of similar quality. All in all, if you have the budget, you can’t go wrong with this choice.

4. Technaflora Recipe for Success Starter Kit

This Technaflora kit lives up to its name by being the perfect starter kit to ensure success in your harvest. It’s the perfect recipe for first-time as well as experienced cannabis growers. The kit contains everything you need for successful gardening.

The kit of the following ingredients and nutrients: root 66, sugar daddy, magical, Rotech cloning gel, awesome blossoms, thrive alive b-1 green and red, B.C grow, and B.C boost.
The package comes with a detailed mixing chart that’s easy enough for new growers to understand and follow. The graph illustrates how to successfully and effectively use the available nutrients together to maximize benefits.

If you’re focused on vegetative growth, you can use the root 66, B.C grows and B.C boost, and in flowering, you can use the awesome blossoms and B.C boost. The magical nutrient, which is a mixture of calcium and magnesium, is going to help with vigor growth, thicker stocks, and stronger stems.

The sugar daddy is a mixture of about twenty amino acids and some part of carbohydrates, amongst other things, to help increase overall plant health.

What We Liked
  • High-performance ten-part organic fertilizer
  • Detailed mixing chart for ease of combination to maximize benefits
  • Root 66, B.C grow, and B.C boost promote veg growth
  • Magical nutrient stimulates vigor growth
  • Sugar daddy increases overall plant health
  • Thrive alive b-1 is great for foliar spraying
What We Didn’t Like
  • Some of the bottles may arrive leaking or damaged
  • Frequent users report issues mixing the ingredients
Final Thoughts

This kit is a truly comprehensive set that includes all of the fertilizer and nutrients that your plants need to thrive. If you don’t want to spend time researching the right type of food for your plants, then the Technaflora box is an easy alternative to piece-mealing together your own solution.

5. Osmocote Flower & Vegetable Smart-Release Plant Food

Osmocote is a nutrient-rich formula that helps with flower and vegetative state growth. The fertilizer is made up of high-nutrient granules that are coated with semi-permeable resin. The resin coating requires low soil temperature to react and to provide your plants with nutrients.

The coating allows water to enter the granules easily as well as dissolve the encapsulated nutrients. When the nutrients are dissolved, they are released based on changes in temperature. Typically, a more significant percentage of the nutrients are freed during warmer growing periods. We love this brand because it’s one of the easiest fertilizers to use. Just scatter a scoopful per four square feet, mix with the soil, and water the plants frequently. The only downside to this mixture is that it has seasonality to it. It’s much more suitable for perennials and seasonal plants.

What We Liked
  • Stimulates strong root development and vigorous top growth
  • Formulated for colorful blooms and flavorful vegetables
  • A great choice for perennials
  • Comes with easy-to-use coated nutrient granules
  • Suitable for containerized planting
What Didn’t Like
  • The packaging is not always secure
  • This fertilizer is not suitable for annual plants or summer harvests
Final Thoughts

The Osmocote Flower & Vegetable Smart-Release plant food is great for seasonal growers who want to optimize their harvest for the particular season they are growing in. It’s straightforward to use and stimulates plant growth to create more aesthetically pleasing plants. If you are concerned with aesthetics and nice-looking buds, this plant food is a great choice that will yield you successful results.

6. Grow More Hawaiian Bud Plant Fertilizer

The Grow More Hawaiian Bud Plant Fertilizer promises to help you grow larger buds without as much work as other marijuana fertilizers. The blend contains plant nutrients from seaweed extract, zinc EDTA, manganese, iron EDTA, copper EDTA, sodium molybdate, boric acid, potassium sulfate, ammonium sulfate, potassium phosphate, and ammonium phosphate.

The application is super easy. Just add the formula to your desired volume of water, then agitate the water until the formula is dissolved.

What We Liked
  • It is water-soluble and urea-free
  • Presence of humic acid is suitable for hydroponics systems
  • Perfect for injection of fertilizer as well as foliar applications
  • High bloom fertilizer designed to produce bigger plants
  • Compatible with multiple growing media
What We Didn’t Like
  • Contains boron, which may be detrimental to your cannabis plants if used long-term
Final Thoughts

This Grow More Hawaiian formula comes highly recommended for use during the later part of the flowering stage. It is designed to send higher strength nutrients to your cannabis plants, which will produce larger blooms and yields. It’s a fan favorite because of it’s versatility and compatibility with other growing systems such as aeroponic, coco coir, organic soils, hydroponics, and soilless systems.

7. Element Flower Fuel Plant fertilizer

The Element Flower Fuel Plant fertilizer consistently produces plants that grow big blooms and more potent flowers. It’s a unique mixture that contains organics, vitamins, amino acids, and nutrients. It is formulated to generate heavier, denser, and larger cannabis yields. It is the ideal bloom additive that delivers fuel for the growth as well as the development of your small or large weed sites. It is formulated to work wonders in hydroponics, coco coir, peat, and soil-based systems. Not to mention that it works just fine with any base nutrients.

This formula is obtained from citric acid, glycine, kelp, sodium molybdate, boric acid, magnesium sulfate, potassium sulfate, and monopotassium sulfate. This high-performance fertilizer is a hundred percent hydroponic grade, as well as soluble bloom plant food that can treat two hundred gallons of water.

What We Liked
  • Contains vitamins, nutrients, and amino acids that support plant growth
  • Includes superior proprietary ingredients aimed at stimulating healthy plant growth
  • 100% hydroponic bloom formula
  • Formulated to promote heavier, denser, and larger yields
  • Can be used with different growing mediums
What We Didn’t Like
  • Doesn’t contain calcium and sufficient nitrogen required for healthy green leaves
Final Thoughts

While this blend doesn’t contain as many of the essential nutrients that other fertilizers have, it’s still a solid choice that will help your plants grow better than they would with no additional nutrients at all. We love that it can be used in addition to other growing mediums and is versatile enough to help throughout all of the plant’s grow phases.

8. J R Peters Inc. Jacks Classic Blossom Booster Fertilizer

J R Peters is a trusted fertilizer brand that creates formulas specifically designed to increase the visual appeal of your cannabis plants. It works by targeting the plant’s leaves and roots and using a superior nutrient ratio of 1:3:2 to substantially improve the quality of the plants.

Compared to conventional fertilizers, the quality of the J R Peter’s blend goes above and beyond to make sure that it incorporates as many individual nutrients as possible. The soil is derived from calcium carbonate, ammonium molybdate, copper EDTA, zinc EDTA, manganese EDTA, iron EDTA, boric acid, magnesium sulfate, potassium nitrate, mono-potassium phosphate, and mono-ammonium phosphate.

For the best results and the highest yields, apply this formula to your plants every seven to fourteen days. It’s safe to use during any growth phase. For indoor cannabis plants, it’s recommended that you use a 1/4 of a teaspoon for every one gallon of water you use to water your plants.

What We Liked
  • Superior nutrient and npk ratio promotes optimum growth
  • Suitable for indoor as well as outdoor cannabis plants
  • It feeds through leaves and roots for maximum absorption
  • Promotes a longer flowering period
  • Easy application for indoor or outdoor plants
What We Didn’t Like
  • May not be compatible with all growing media
Final Thoughts

We recommend this formula because it comes with a set of very easy to understand instructions that read more like a guide on growing marijuana indoors, rather than a guide on how to use the fertilizer itself. You can use the formula during pretty much any stage of growth and it will work with the soil to increase the number of blooms and the bloom size. One downside is that it might not be as compatible with smaller grow boxes as it is with larger grow tents or grow rooms.

9. Botanicare Growilla Veg & Bud Plant Fertilizer

This is an organic plant fertilizer designed specifically to use on cannabis plants in the flowering phase. It contains all the ingredients required for plants to thrive in all growth stages. However, it’s purposefully designed to work well with plants while they are flowering. Like a lot of the fertilizers on this list, it contains fish meal, earth worm castings, and bat guano and other natural ingredients that provide a wide range of beneficial microbes and plant food for your weed vegetation.

Unlike conventional plant foods and fertilizers out there, the Growilla Bud is formulated to safely and effectively supply your plants with the necessary nutrients for development. It is designed for use in coco coir, soilless mixes, and soil garden-based grow media. It also works well when mixed with other bloom supplements to encourage even higher yields.

What We Liked
  • It’s an organic and natural plant fertilizer that’s safe for your weed
  • It is a rich source of fish meal, earth worm castings, and guano
  • Can be used with multiple grow mediums, including coco, soilless, and soil
  • Fast shipping times
What We Didn’t Like
  • May not break down fast enough
  • Strong odor makes it not ideal for use in small, indoor spaces
Final Thoughts

The Botanicare nutrient set is a fine choice when it comes to growing marijuana indoors. It utilizes all of the right compounds to create an excellent product. The one thing we don’t like about this blend is that it is not ideal for small, indoor grow areas. Because it uses so many organic ingredients, it has a powerful odor that might make for an unpleasant experience if you are growing in a small space.

10. General Hydroponics GH5312 CaMg+ Plant Nutrition

Are you in search of a calcium and magnesium supplement for your cannabis? Look no further than the General Hydroponics CaMg+.

This formula will help to optimize the nutrition of your weed plants, resulting in superior growth as well as vibrant flowering.

This formula is a blend of magnesium and calcium. Therefore, you can use it whenever your plants require extra soluble magnesium and calcium.

Apart from magnesium and calcium, this formulation also contains sugar chelates and organic acids. The acids are low molecular weight and may facilitate fast transport of the supplement into the plant.

The application is a bit straightforward. Add one teaspoon of the supplement per gallon of water for light feeding, and two teaspoons per gallon for heavy feeding.

What We Liked
  • Optimizes plant nutrition to enhance growth and flowering
  • Easy application, 1 tsp. for light feeding, 2 tsp. For heavy feeding
  • Organic acids facilitate fast transport into your cannabis plants
  • Suitable for most growing media
What We Didn’t Like
  • May experience a significant drop in pH after mixing

11. General Hydroponics BioThrive Plant Food

The BioThrive Plant Food by General Hydroponics provides your weed plants with essential nutrients that are necessary for blooms and larger yields.

It’s a unique vegan formula that doesn’t contain any live matter such as earthworm castings, or other animal derivatives. It uses purely plant-based ingredients to stimulate beneficial microbial activity within the roots of the plant. This formula is mostly derived from soybean meal, sodium molybdate, rock phosphate, potassium sulfate, potassium borate, molasses, magnesium sulfate, ferric sulfate, and alfalfa meal.

It also comprises of non-plant food ingredients for feeding soil microbes, such as cane sugar and humic acids (obtained from Leonardite).

When you use it with potting mixes, add four teaspoons of mixture per gallon of water during heavy feeding. During light feeding, they recommend using two teaspoons per gallon of water.

What We Liked
  • It is a natural and pure vegan formula that will not harm your plants
  • Benefits all plants during blossoming and fruiting
  • Mineral and plant extracts stimulate beneficial microbial root activity
  • Easy application for both hydroponics and potting mixes
What We Didn’t Like
  • May experience problems balancing pH
Final Thoughts

We love how easy the application of this fertilizer works. When you buy it, it comes with detailed instructions on how to use it with any grow material and grow phase. It works well with most sizes of grow space and includes all of the essential nutrients your cannabis needs to thrive.

12. Maxicrop Pure Seaweed Extract Soluble Powder

This Maxicrop plant food is formulated from the premium seaweed reaped from the Norwegian coastline. An ingredient that you don’t see very often, but that cannabis seeds thrive off. According to the manufacturer, this supplement has a 17% soluble potash that is suitable for grow rooms containing weed and other houseplants.

It contains natural growth stimulants that not only initiate cell growth but also promote fast growth of stem and roots. Another impressive attribute of this plant food is the ability to be mixed with other fertilizers. For example, you can effectively mix this with Azomite and should not expect any disruptions in your growth cycle.

This product can be used in different growth media, including aquaponic systems, which can’t be said for a lot of the other fertilizers on this list. Additionally, it incorporates a wide range of fish species, including bluegill and tilapia, that help your plant grow larger and more efficiently.

What We Liked
  • Made of premium seaweed that is very beneficial to plants
  • Natural growth stimulants promote fast stem and root development
  • Can effectively be mixed with other fertilizers, such as Azomite
  • Works great with aquaponic systems
What We Didn’t Like
  • The powder form of Maxicrop may not be suitable for foliar application
Final Thoughts

The additions of Azomite and fish species, make this one of the most nutrient-dense fertilizer blends we’ve seen. You might think that these ingredients create a harsher grow environment, but on the contrary, the fertilizer if very gentle, yet effective. It also does not have a strong smell which makes it ideal for smaller grow spaces.

13. Cutting Edge Solutions UJB:2603 Uncle John’s Blend Growing Additive

Uncle John’s Blend Growing Additive from Cutting Edge Solutions uses potassium to stimulate healthier photosynthesis cycles. Because you’re increasing the metabolic rate of your plants, you can expect a healthier, and more perky, plant. The low molecular weight attributes to a clean spray that doesn’t sit heavily on the plants.

It’s also tricky to overfeed with a potassium mixture. Although using Uncle John’s Blend Growing Additive is only necessary twice a week, many marijuana growers report using it more often without any issue.

  • Complex, the potassium-based mixture
  • Increases metabolic rate
  • Low molecular weight
What We Liked

There’s so much to love about Uncle John’s Blend Growing Additive. Cutting Edge Solutions outdid themselves with this formula. First, we appreciate the clean spray as it doesn’t leave a heavy build-up on your plants.

Second, we like how the formula doesn’t try to overload the plants with nutrients. Instead, it uses potassium to stimulate healthy photosynthesis. Finally, we like that it’s usable throughout the entire growth cycle. You can keep giving it to your plants, and it’s not a detriment to their bloom or vegetation states.

What We Didn’t Like

The only thing we don’t like about Uncle John’s Blend Growing Additive is the price. Although nutrients are an investment in your plant’s well-being and ultimate bloom, these are pricey. The formula doesn’t claim to use organic compounds, which might warrant the price.

Final Thoughts

Overall, Uncle John’s Blend Growing Additive from Cutting Edge Solutions is a fantastic nutrient additive. The quality is above standard, it’s difficult to overfeed, and you can use the same formula throughout the growth cycle.

These qualities combine to make a perfect formula for first-time growers. If you’d rather spend a bit more money to ensure you grow cannabis that’s high quality, Cutting Edge Solutions makes an excellent formula.

There are a variety of other options from Cutting Edge Solutions as well. Our pick for the potassium-based formula was the focus on improving photosynthesis. Because it’s the basis for all plant’s nutrient absorption, this product is the best option for creating the right environment for healthy plants.

14. Orga Grow Holland Organic Nutrients For Marijuana Plants – Liquid Fertilizer For Hydroponic

From Orga Grow Holland, we have organic nutrients and liquid fertilizer option. This formula was developed in Holland through years of trial and error. Although they advertise it as made for any plant, it’s designed explicitly for cannabis growth.

The formula here is a 3-step system to aid your plants from initial planting and well into their bloom. The first step is a root stimulator which acts to encourage root growth and generation.

The second step is a growth stimulant. The growth stimulant will help you produce a higher yield. The third and final step is an abundant flowering formula.

  • Simple formula
  • Organic
  • 3 step growth system
What We Liked

We like that this formula is a full system. For experienced growers who can accurately track their plant progression and identify when nutrients are necessary, this setup is a great option. The root stimulator isn’t a formula you see very often.

Getting your plants to take root properly is a frustration that many growers share. The root stimulator is the biggest win from this formula.

What We Didn’t Like

We don’t like that this doesn’t offer a lot for the new growers. If you’re new to growing, you might miss key signs that indicate it’s time to switch to the next step. There is a risk with both the growth stimulant and that flowering formula of overfeeding.

These issues kept the Orga Grow Holland formula from being the best nutrients and fertilizer for growing weed.

Final Thoughts

For the price, this is a quality product. It’s organic and is easy to use in coco fiber, soil, clay pebbles, and hydroponic systems. The product itself is versatile, but it relies on the user to have some knowledge about proper feeding and handling of cannabis.

The Orga Grow Holland isn’t exceptionally well-known, but it offers quality organic products that can assist experienced growers in increasing their yield and boosting their flowering phase.

15. 13Essentials Foliar Spray Fertilizer

This formula isn’t intended for marijuana use specifically. The 13Essentials formula does wonders for nearly any plant though. With 13Essentials you can be sure that your plants are getting nearly all the macronutrients and micronutrients they need. It’s difficult to overfeed with this nutrient option, although it is possible, so be careful!

  • Foliar feed system
  • 13 added nutrients
  • Designed for faster absorption
What We Liked

We enjoyed that the 13Essentials focused on what plant’s need to carry out their normal lifecycle. With potassium and phosphorous as the base, it also uses boron, magnesium, calcium, iron, zinc, manganese, copper, and more.

The wide array of macro and micronutrients in this formula is causing many growers to use 13Essentials.

What We Didn’t Like

Unfortunately, the price and the results don’t add up. The price is pretty steep, considering that a container only holds one ounce. Then you must mix it down with the teaspoon. However, each teaspoon significantly diminishes your one ounce supple.

Then the results are mixed. Sometimes it works great; the plants are a receptive and slow response to the additive. However, there are regular reports that the formula didn’t do anything.

Final Thoughts

If you’re looking for a fertilizer or nutrient additive that will have an outstanding impact on your plants, this is not the formula for you. However, if you’re looking for something a little extra to give your plants, 13Essentials works well.

We don’t recommend this product to anyone trying to specifically increase their yield, bud growth, bud size, or potency. The 13Essentials formula is purely to ensure your plants are getting a large volume and variety of both macronutrients and micronutrients.

How to Choose The Right Fertilizer

What goes into choosing the right nutrients and fertilizer? We just broke down fifteen of our favorites, but even this list might be overwhelming if you’re not sure what to look for. There are key factors that you should consider when making the final choice of which fertilizer you want to use for your grow operation. The right fertilizer and nutrients should contain everything that your plants need, but they should be a good fit for how you are growing cannabis. Depending on your grow space, the seeds you are using, and the type of cannabis plants you want to grow, there are specific things you should look for.

The first thing to understand is that any type of cannabis plant needs specific elements to thrive. These elements, also known as micronutrients, include mineral and non-mineral elements.

Every cannabis plant needs the following to survive:

  • Nitrogen
  • Hydrogen
  • Oxygen
  • Phosphorus
  • Sulfur
  • Potassium
  • Calcium
  • Carbon Dioxide
  • Magnesium

If you want to simplify, the main three, most basic nutrients your plants need to grow are nitrogen, potassium, and phosphorus (npk). When looking for these nutrients in your fertilizer, you should look for a number 3 printed on the bag. This will indicate that it contains the three essential nutrients you need.

Once you have these three ingredients covered, almost everything else within the blend becomes extra. And while your plants will survive with just the basic NPK, they will not grow as well or as abundantly as they would when you incorporate other macronutrients. To get the most out of your seeds, you need to incorporate a wide array of macronutrients because it’s likely that your plants can’t get everything they need just from fertilizer. This need has driven the growing community to develop several fantastic nutrient additions.

When researching additional nutrients, make sure that you look for ones with a water-soluble base. Whether the nutrients you’re giving your plants are liquid or tablets, they need to disperse with water. Since the nutrients most effectively enter a plant through the roots, a lot of growers drip the nutrients into the water supply or soil.

Aside from the macronutrients, in order for your plants to truly thrive, you need also to incorporate trace amounts of these elements:

  • Chlorine
  • Cobalt
  • Boron
  • Iron
  • Zinc
  • Molybdenum
  • Silicon
  • Copper
  • Manganese

These elements contribute to the long-term health of the plant and help it through the flowering stage. Not using these micronutrients won’t kill your plant, but it can greatly affect bud growth and potency. The goal of using additional nutrients is to create a diverse and healthy ecosystem of microbes for your plants so that they produce the best results possible.

If you’re new to growing, it’s a good idea to use a pre-made fertilizer with organic nutrients and materials. When it comes to composting or creating your own nutrients, this route has a high risk of failure. Finding the proper nutrients and fertilizer for your plants will be a labor of love, but hopefully, with these reviews, you can find the best options for you!

The Clear Winner…

Any of the products on this list will help you grow healthier and more potent plants. But one product, in particular, stands out as the most comprehensive and easiest solution to incorporate into your growing.

Our pick for the top nutrient and fertilizer is the General Organics Go Box. We’re going with this one as the top choice because it comes, which comes with a wide variety of products that you can use at various stages of growth. With root stimulant, vegetative growth support, and bio bud, you can be sure that your plants are well taken care of at every stage of their lifecycle.

It’s not easy identifying the right nutrients to add to your plants. If you’re a new grower, then you might not even know where to look or where to start. We hope that by breaking down our top picks for the best fertilizers for growing marijuana that you have a resource to turn to that will help you grow your knowledge and grow higher quality cannabis.

If you're growing your own legal cannabis, you don't want to get this wrong. Read to find out what's the best nutrients and fertilizer for cannabis.