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Which Nutrients Are Best For Growing Cannabis?

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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

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.”

Dyna-Gro

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.

Best NPK Ratio for Veg and Flower

Waiakeauka
Well-Known Member
scunkworm
Active Member
scunkworm
Active Member
elduece
Active Member
homebrewer
Well-Known Member

Your info is pretty mixed up there. 3-1-2 for veg though I’ve found 1-1-1 works just as well. 1-3-2 for flower is by far the best NPK ratio I’ve tried thus far.

Too much P locks out Zinc, Iron, and Copper. Not sure where you’re getting N from.

cannabis love
Well-Known Member
Rotweiller
Well-Known Member

Hello Waiakeauka. I’m not sure if this will help you or not but i found this on another website and it made sense to me –
Cannabis requires a 1:2 ratio of P to K throughout all stages of it’s growth.

It’s worth stating for the record the actual ratios of N, P and K that cannabis requires through it’s life cycle:

Vegetative Stage
N – P – K
3 – 1 – 2

Flowering Stage
N – P – K
1 – 1 – 2

Final Flowering Stage
N – P – K
0 – 1 – 2

To translate this into a 12 week schedule for a typical Skunk type such as Cheese or Psychosis would give something along these lines:

Veg week 1: 3 – 1 – 2
Veg week 2: 3 – 1 – 2
Flo week 1 : 3 – 1 – 2
Flo week 2 : 3 – 1 – 2
Flo week 3 : 1 – 1 – 2
Flo week 4 : 1 – 1 – 2
Flo week 5 : 1 – 1 – 2
Flo week 6 : 1 – 1 – 2
Flo week 7 : 0 – 1 – 2
Flo week 8 : 0 – 1 – 2
Flo week 9 : 0 – 0 – 0
Flo week 10: 0 – 0 – 0

This schedule reduces the Nitrogen two weeks into the 12/12 period which will assist in stopping the vertical growth (stretch). It cuts out all Nitrogen after 6 weeks which will result in a less leafy, smoother burning end product with greater density to the flowers. The last two weeks of plain water is sufficient to leach out all accumulated salts and give a clean end product. Three week flush as advocated by some really isn’t necessary if the Nitrogen is cut out after 6 weeks. The people using a three week flush tend to use Canna nutes which have too much N in them for late flowering and this is why they get a benefit from flushing for three weeks.

Hope that makes sense. Despite all the crap the nute companies fill our heads with about the need for all kinds of fancy bottles, you really don’t need any of them. Cannabis is a simple plant, a weed in fact, and all it needs is the correct NPK at the correct time plus a full range of trace elements, that is hard fact and no amount of BS an marketing from the nute companies will ever change that fact.

Anyway Hope this helps you a little bit ? Good luck and Happy Growing

uhavealighter?
Active Member

Hello Waiakeauka. I’m not sure if this will help you or not but i found this on another website and it made sense to me –
Cannabis requires a 1:2 ratio of P to K throughout all stages of it’s growth.

It’s worth stating for the record the actual ratios of N, P and K that cannabis requires through it’s life cycle:

Vegetative Stage
N – P – K
3 – 1 – 2

Flowering Stage
N – P – K
1 – 1 – 2

Final Flowering Stage
N – P – K
0 – 1 – 2

To translate this into a 12 week schedule for a typical Skunk type such as Cheese or Psychosis would give something along these lines:

Veg week 1: 3 – 1 – 2
Veg week 2: 3 – 1 – 2
Flo week 1 : 3 – 1 – 2
Flo week 2 : 3 – 1 – 2
Flo week 3 : 1 – 1 – 2
Flo week 4 : 1 – 1 – 2
Flo week 5 : 1 – 1 – 2
Flo week 6 : 1 – 1 – 2
Flo week 7 : 0 – 1 – 2
Flo week 8 : 0 – 1 – 2
Flo week 9 : 0 – 0 – 0
Flo week 10: 0 – 0 – 0

This schedule reduces the Nitrogen two weeks into the 12/12 period which will assist in stopping the vertical growth (stretch). It cuts out all Nitrogen after 6 weeks which will result in a less leafy, smoother burning end product with greater density to the flowers. The last two weeks of plain water is sufficient to leach out all accumulated salts and give a clean end product. Three week flush as advocated by some really isn’t necessary if the Nitrogen is cut out after 6 weeks. The people using a three week flush tend to use Canna nutes which have too much N in them for late flowering and this is why they get a benefit from flushing for three weeks.

Hope that makes sense. Despite all the crap the nute companies fill our heads with about the need for all kinds of fancy bottles, you really don’t need any of them. Cannabis is a simple plant, a weed in fact, and all it needs is the correct NPK at the correct time plus a full range of trace elements, that is hard fact and no amount of BS an marketing from the nute companies will ever change that fact.

Anyway Hope this helps you a little bit ? Good luck and Happy Growing

I back this statement up for sure! I have seen many experiments where people are trying to compare advanced nutrients to other nutes and this company has always clearly won. Mostly because their nutrients were developed from cannabis and not tomatoes. Maybe we should blend cheaper nutes to the AV’s npk ratios? I believe it would be their n-p-k ratios over anything else. They do also have a lot of boron probably for some good reason.

All of their nutrients schedules for the flowering stage, with additives or without, comes very close to 1-1-2-0.5 Ca-0.25 Mg. At the last two weeks, however, they have it closer to 2-3-4-1 Ca-0.6 Mg. And obviously a flush at the end.

Advanced Nutes seems to have a lot of amino acids, humic acid, sugars, and microbes too.

I also like that they don’t have calcium mixed with phosphorous and magnesium in concentration.

But I will stay away from them and mix up cheap, microbe friendly nutes using AV’s ratio’s.

There have been many people that say you need to use nutes that are designed for MJ, so what is the ideal NPK ratio for Veg and Flower? Many people say…