There are a lot of ways for your hydroponic system to fail:
- Low light or incorrect light/dark cycles
- Poor ventilation
- Poor water oxygenation
- Stagnant, unproductive water
- Disease and pests
But nutrient deficiency?
That’s one of the easiest things to fix!
There are just 4 easy steps to create the best hydroponic nutrients:
- Figure out what nutrients your plants need.
- Buy them.
- Mix them into your water source.
- Grab a beer.
This guide covers them all.
(OK, the beer is up to you, but we’re happy to make some suggestions.)
Let’s get growing.
7 Best Hydroponic Nutrients: Quick Picks
- Best Hydroponic Nutrients: General Hydroponics Flora Series
- Runner Up: FoxFarm Liquid Nutrient Trio
- Best For Lettuces & Herbs: General Hydroponics MaxiGrow
- Best For Seedling Stage: Clonex Clone Solution & Seedling Nutrient
- Best For Vegetative Stage: Root Farm Stage 2 All-Purpose Supplement
- Best For Fruiting Stage: General Hydroponics MaxiBloom
- Best Late-Stage Yield Booster: General Hydroponics KoolBloom
16 Essential Nutrients Your Plants Need
Your plants need 16 different nutrients to thrive in your hydroponic system.
The good news is you don’t need to worry about all 16. For the most part, you only need to worry about the 3 Primary Nutrients:
- Nitrogen (N)
- Phosphorus (P)
- Potassium (K)
(But you can easily boost your plant’s growth and productivity by adding the Secondary Nutrients as well.)
Before we get to our list of the best hydroponic nutrients below, here’s a quick overview of plant nutrition.
(This stuff is super important and easy to understand.)
Note: Our ULTIMATE Guide To The 16 Essential Hydroponic Nutrients is the Internet’s best resource on the subject (maybe I’m biased) so check that out, too.
Environmental Nutrients
Nutrients: Hydrogen (H), Carbon (C), Oxygen (O)
Environmental nutrients are provided by air and water, so you don’t need to add them with a fertilizer or nutrient mix.
Hydrogen and oxygen are provided by water, so make sure your water is sufficiently aerated, especially for deep water culture hydroponics.
Carbon is provided by the air, so make sure you have sufficient ventilation, especially for grow rooms and grow tents.
Primary Nutrients
Nutrients: Nitrogen (N), Potassium (K), Phosphorus (K)
These are the super-important nutrients you need to provide for your plants, usually with an NPK mix where N-P-K are the elemental symbols for each nutrient.
Each nutrient has a different role in plant growth:
- Nitrogen: Helps the stems and leaves grow
- Phosphorus: Helps the roots and fruit grow
- Potassium: Aids in photosynthesis for rapid overall growth
The ratio of N, P, and K in your hydroponic nutrient mix depends on two factors:
- The type of plant(s) you’re growing
- Their stages of growth
Let’s say you’re growing hydroponic peppers. How do you tailor your NPK mix for optimal growth?
- Early in their life cycle, pepper plants need a lot of potassium (for efficient photosynthesis) and nitrogen (for leaf development) with added phosphorus for their roots.
- As plants hit their primary growth phase with roots sufficiently developed, nitrogen becomes more important and phosphorus less. This emphasizes stem and leaf growth.
- Finally, as pepper plants enter the flowering and fruiting phase, you want to cut back on nitrogen and increase both phosphorus and potassium. This emphasizes fruit development and prevents your plants from wasting their energy growing more stems and leaves.
By combining dialed-in NPK concentrations with growth phase-specific lighting, you’ll see bigger yields than you ever thought possible.
Secondary Nutrients
Nutrients: Calcium (Ca), Magnesium (Mg), Sulfur (S)
You probably should add these nutrients to your hydroponic system, almost like a booster. They’re required in much smaller quantities and can be found in two common products:
- Calcium Nitrate provides Calcium
- Epsom Salts provide Magnesium and Sulfur
It doesn’t take much — just toss 2 tablespoons of each per gallon of water into your nutrient mix and you’ll be good to go.
Micronutrients
Nutrients: Boron (B), Chlorine (Cl), Manganese (Mn), Iron (Fe), Copper (Cu), Zinc (Zn), Molybdenum (Mo)
Micronutrients are required in trace amounts and don’t need to be added to a nutrient mix. Generally, the seed from which a plant germinates has enough of these nutrients to sustain the plant for its entire life cycle.
However, deficiencies can crop up, especially if you’re cloning your plants for multiple generations, and should be addressed as needed. This guide has a great list of warning signs to look out for.
Wet vs Dry Fertilizer: Which Is Better?
Fertilizers come in one of two forms: wet (liquids) or dry (powder/crystals).
Wet fertilizer comes with all of the nutrients already dissolved in water, which makes it incredibly easy to use. Unfortunately, because wet fertilizer already is dissolved in water, you’re paying for that water (usually in the form of shipping costs).
Dry fertilizer comes as powder or crystals that you need to mix yourself. This makes them much more economical but there’s a little extra thinking and work involved.
Wet vs Dry: Which Do We Prefer? Honestly, it doesn’t really matter. If you opt for wet fertilizer (like our top pick, the General Hydroponics Flora Series) you’ll add about 1-3 teaspoons of solution per gallon of water. The product I just linked to comes in 1-quart volumes (192 teaspoons per quart) which is enough for 60-80 gallons of nutrient mix. You’ll be set for a while.
Best Hydroponic Nutrients: General Hydroponics Flora Series
Overview: The General Hydroponics Flora series is the easiest, most versatile hydroponic nutrient system available. Designed to take your fruiting or flowering crops from seed to harvest, it includes three specially-designed mixes for each stage of development that work in harmony for explosive growth and impressive yields.
| Best Use | All stages from seedling to flower |
| NPK | FloraGro: 2-1-6 FloraMicro: 5-0-1 FloraBloom: 0-5-4 |
| Wet or Dry | Wet |
| Weight/Volume | 3 x 1 quart |
| More Info | View on Amazon → |
General Hydroponics is all over this list, and with good reason: They’re the industry leader in plant nutrition and have the best line of hydroponic nutrients.
The Flora Series is designed for an elite combination of performance and ease of use, giving you everything you need to take your crop from seed to harvest without much effort.
The three-solution series is optimized for each stage of flowering/fruiting plant development:
- FloraGro for seedling root development
- FloraMicro for vegetative and early flowering
- FloraBloom for final fruit production
Each solution can also be purchased separately, but I think they work best in combination. You can also buy them in different quantities and/or as a dry fertilizer, but this 1-quart wet fertilizer product is their most popular.
If you’re planning on growing lettuces or herbs, you probably don’t want the Flora Series (because you don’t need the flowering mix).
Instead, you can easily create your own two-stage nutrient mix with our top picks for seedlings development and big lettuce/herb vegetative growth:
- Seedlings: Clonex Clone & Seedling Nutrient
- Vegetative Growth: General Hydroponics MaxiGrow
But if you’re growing flowering plants like tomatoes, peppers, or cannabis, the General Hydroponics Flora Series is a no-fuss way to achieve enviable results.
Runner Up: FoxFarm Liquid Nutrient Trio
Overview: Like the aforementioned General Hydroponics Flora Series, the FoxFarm Liquid Nutrient Trio has you covered from seed to harvest with a three-stage system that’s easy to use.
| Best Use | All stages from seedling to flower |
| NPK | Tiger Bloom: 2-8-4 Grow Big: 6-4-4 Big Bloom: 0-0.5-0.7 |
| Wet or Dry | Wet |
| Weight/Volume | 3 x 1 quart |
| More Info | View on Amazon → |
Another awesome brand with an easy, three-solution nutrient mix is FoxFarm.
Like the General Hydroponics Flora Series, this FoxFarm Liquid Nutrient Trio is designed to take your plants from seed to harvest with three specially-formulated nutrient solutions:
- Tiger Bloom (2-8-4) for both root and flower production
- Grow Big (6-4-4) for stem and leaf growth
- Big Bloom (0-0.5-0.7) for final fruit production
A few things that make this series different than the General Hydroponics series above:
- FoxFarm’s Liquid Nutrient Trio doesn’t have a dedicated seedling formulation, which is why we recommend using Tiger Bloom for early-stage growth. Though it has “Bloom” in its name, Tiger Bloom’s high phosphorus concentration also stimulates strong root growth.
- The final Big Bloom mix doesn’t have much in the way of N, P, or K! Instead, it’s packed with organic fertilizers like bat guano and earthworm casings, which enhance fruit production naturally without risking damage to your delicate crops in the form of fertilizer chemical burns.
For more information about FoxFarm and their products, check out our FoxFarm Nutrients Review.
Best For Lettuces & Herbs: General Hydroponics MaxiGrow
Overview: Packed with 14% potassium by weight, General Hydroponics MaxiGrow is designed for huge vegetative growth. Potassium aids in photosynthesis for rapid growth, which is especially important for leafy greens and herbs, since that’s what you’ll be harvesting.
| Best Use | Maximum vegetative growth for lettuces and herbs or as a Stage 2 fertilizer for all fruiting/flowering plants |
| NPK | 10-5-14 |
| Wet or Dry | Dry |
| Weight/Volume | 2.2 lbs |
| More Info | View on Amazon → |
The General Hydroponics Flora Series and FoxFarm Liquid Nutrient Trio are great for flowering plants, but what if you’re growing leafy greens or herbs?
Then you want General Hydroponics MaxiGrow.
Nitrogen and potassium-rich, MaxiGrow is formulated for big-time vegetative growth. Lower in root-friendly phosphorus, it’s best-used as a stage two nutrient mix when you’re ready to focus on stem and leaf growth.
For that first stage, our next pick has you covered.
Best For Seedling Stage: Clonex Clone & Seedling Nutrient
Overview: A clone-specific formulation designed to propagate cuttings and germinated seeds, Clonex Clone & Seedling Nutrient is highly-concentrated to encourage rapid root development, ensuring your next crop gets started on the right root.
| Best Use | Cloning and starting seedlings |
| NPK | 1-0.4-1 |
| Wet or Dry | Wet |
| Weight/Volume | 1 quart |
| More Info | View on Amazon → |
Clonex Clone & Nutrient Solution is designed for robust root development of both clones and seedlings. While its NPK numbers look uninspiring, it’s packed with trace nutrients and root-enhancing agents and works well in cloning machines, ebb and flow systems, NFT systems, and really anything else you can think of.
It also works well for struggling plants that need a boost to give them a little more life.
Best For Vegetative Stage: Root Farm Stage 2 All-Purpose Supplement
Overview: Like General Hydroponics MaxiGrow, Root Farm Stage 2 All-Purpose Supplement is potassium-rich for maximum vegetative growth.
| Best Use | Maximum vegetative growth for lettuces and herbs or as a Stage 2 fertilizer for all fruiting/flowering plants |
| NPK | 2-3-7 |
| Wet or Dry | Wet |
| Weight/Volume | 1 quart |
| More Info | View on Amazon → |
This Root Farm Stage 2 All-Purpose Supplement is like General Hydroponics MaxiGrow but has a higher concentration of potassium for robust photosynthesis (strong overall growth) and more phosphorus than nitrogen to focus on the transition from leaf to fruit development.
Summary: Root Farm Stage 2 is geared more toward general plant growth and photosynthetic efficiency versus MaxiGrow’s leaf-focused formulation. That makes this product ideal as a vegetative stage mix for flowering plants.
When you’re ready to get flowering started, you’ll want these next two hydroponic nutrients.
Best For Fruiting Stage: General Hydroponics MaxiBloom
Overview: When it’s time to flower, General Hydroponics MaxiBloom has you covered with 15% phosphorus and 14% potassium by weight. High phosphorus concentrations induce blooming while potassium continues to promote robust photosynthetic energy creation for strong yields.
| Best Use | Induce strong fruiting/flowering |
| NPK | 5-15-14 |
| Wet or Dry | Dry |
| Weight/Volume | 2.2 lbs |
| More Info | View on Amazon → |
General Hydroponics MaxiBloom is all about getting the flowering phase started on the right foot. With high concentrations of phosphorus and potassium, you get photosynthetic efficiency directed at fruit production.
MaxiBloom works great as your final nutrient mix, but there’s one final mix you can use to finish with a bloom.
Best Late-Stage Yield Booster: General Hydroponics KoolBloom
Overview: Kick flowering into overdrive with General Hydroponics KoolBloom’s 45% phosphorus by weight. That’s triple the bloom-boosting concentration of MaxiBloom and is perfect for that final flowering push before harvest.
| Best Use | Late-stage yield boosting for fruiting/flowering plants |
| NPK | 2-45-28 |
| Wet or Dry | Dry |
| Weight/Volume | 2.2 lbs |
| More Info | View on Amazon → |
MaxiBloom has nearly equal parts phosphorus and potassium. KoolBloom kicks that up to an insane level with nearly twice as much phosphorus as potassium for full-powered fruit development.
Designed for ripening your fruits right before harvest, KoolBloom encourages the production of fragrant essential oils to make your final product a complete sensory experience.
For cannabis growers, KoolBloom stimulates crystal development, creates flowers so heavy they bend the stems, and results in a powerfully fragrant final product that can’t be beaten.
Best Hydroponic Nutrients: Final Thoughts
Like every aspect of your hydroponic system, your nutrient mix is crucial to the health and productivity of your plants. It’s also one of the most easily adjustable variables that can take your crops from lackluster to spectacular.
- For beginners looking for easy seed-to-harvest nutrition, it doesn’t get better than the General Hydroponics Flora Series.
- For lettuce and herb farmers, you’ll get your biggest yields with General Hydroponics MaxiGrow.
- To get your seedlings started on the right root, Clonex Cloning Solution & Seedling Nutrient is the tried-and-true winner.
- For the best yields (and irresistible aromatics), use a combination of General Hydroponics MaxiBloom and KoolBloom.
If you have any questions about choosing the best hydroponic nutrients for your setup, comment below.
