Humboldts Secret

Humboldts Secret Base A B Liquid Hydroponic Fertilizer Complete Hydroponic Nutrients for Indoor and Outdoor Plants Supports Healthy

265+ bought in the past month

$39.97

About this item

  • Packaging Update: You may receive previous or updated packaging during our transition. Same formula, same performance. Fuel Plants With Complete Nutrition - Humboldts Secret Base A and B delivers a full-spectrum formula with nitrogen, phosphorus, potassium, calcium, and magnesium. These premium plant nutrients support steady development, vibrant leaves, and bold blooms for vegetables, herbs, flowers, and indoor plants. Our formula is ideal for those who want lasting plant health and consistent feeding every single week.
  • Simplify Your Feeding Routine: Our easy two-part system requires no complex schedules or guesswork. Just mix equal parts of Base A and B with every watering. This consistent approach supports better absorption and stronger plants across hydroponic gardening, coco coir, or traditional soil setups. Measuring and mixing take just seconds each time.
  • Compatible With Any Grow Setup: Humboldts Secret nutrients are built for results in deep water culture, aquaponics, pots, raised beds, or coco. Our Base A and B are trusted as reliable hydroponic nutrients by both home growers and commercial cultivators. Works great with timers, tanks, or hand watering systems.
  • Professional Results Without the Hassle: Our pH-balanced, fully water-soluble formula mixes fast and clean. It won’t clog lines or leave residue, making it ideal for hand-watering or automated systems. Humboldts Secret delivers dependable liquid plant food for every stage of plant development. Start seeing results in just a week.
  • Support Every Plant With One Formula: From leafy greens and flowering plants to trees, herbs, and houseplants, our Base A and B system delivers the core nutrients all plants need. Use this proven fertilizer for indoor plants across your entire garden for consistent, visible results. Safe for hydroponics, soil, containers, or beds.
$39.97

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Delivery13 Apr – 17 Apr
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Product details

BrandHumboldts Secret
Item Weight32 Ounces
Item FormLiquid
Liquid Volume64 Fluid Ounces
Specific Uses For ProductHydroponics

Technical specifications

brandHumboldts Secret
item_weight2 pounds
item_formLiquid
liquid_volume64 Fluid Ounces
specific_uses_for_productHydroponics
manufacturerHumboldts Secret
number_of_items1
upc648260730437
unit_count64.0 Fluid Ounces
package_dimensions9.29 x 7.83 x 4.8 inches
item_model_number4316245515
best_sellers_rank#9,495 in Patio, Lawn & Garden ( See Top 100 in Patio, Lawn & Garden ) #401 in Garden Fertilizers
is_discontinued_by_manufacturerNo

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Customer reviews

4.53,363 ratings

Customers say

Customers find this hydroponic fertilizer to be a fantastic product that works well in both hydroponic systems and traditional planting. Customers disagree on the product's effectiveness, with some reporting their plants appear healthy while others say it completely destroyed their plants.

★★★★★

Great Fertilizers

dlbekkerMarch 6, 2026✓ Verified purchase

It is a great grow and bloom fertilizer. I'm using all of their products for an inside grow. Read more

★★★★★

Hydroponic nutrient

Kevin M. SearsFebruary 15, 2026✓ Verified purchase

This plant food works great with the plants in our grow tent, easy to measure and introduce into DWC! Very fast shipping, although the company needs to find a better way to seal container as they leaked a bit! Read more

★★★★★

Hugely Successful Grows with Humboldt's Secret

Jason GonzalezJanuary 20, 2026✓ Verified purchase

I use the whole Humboldt's Secret nutrient line on plants grown indoors in tents with automated lighting, circulation and exhaust fans and manual feeding, watering, temperature and humidity controls. My flowers are cup quality, every time. Top quality nutrients, broad spectrum, easy schedule and dosing and super reasonable compared to other brands with comparable offerings. On average, I'd say my return on investment in yield:nutrient is about 50:1. Hard to argue that. I'm a believer. Read more

★★★★☆

Measurements gore

Ed SpencerApril 30, 2024✓ Verified purchase

This stuff seems to work, but the wording on the back is hilariously ambiguous, and I'm sure I'm adding the wrong amounts. It says "5-9ml/GAL A + B". First up, mixing metric and imperial measurements like that is confusing - it's a bit like saying "5-9 inches per kilometer". Beyond that, this wording could mean: 1) "5-9ml of A + B combined per gallon of water you are adding" 2) "5-9ml of A and 5-9ml of B per gallon of water you are adding" 3) "5-9ml of A + B combined per gallon of water in your tank" 4) "5-9ml of A and 5-9ml of B per gallon of water in your tank" I think it's option 2, but as a hydroponics noob I could see it being 3 or 4 too (maybe the plants pull all the nutrients out of the tank water so you need to replenish - dunno). Here are a few formulations of what I think they mean, using a consistent measuring system: * mix 1-2ml of each of A and B per liter of water you add * mix 1-2 parts of each of A and B with 1000 parts water, then add to your tank * mix 0.2-0.3 fl oz of each of A and B per gallon of water you add You probably boost your chances by sticking to metric here as they're calling for a dilution of roughly a thousand to one, and that's hard to do with imperial. Also, invest in a pipette because eyeballing 9ml is a challenge for the best of us. Read more

★★★★★

Awesome hydroponic or soil solution!

MKNFebruary 17, 2026✓ Verified purchase

I love this so much that this is a re-order! This product is fantastic for hydroponic systems or traditional planting. I found it worked even better than the supplied food for Aerogarden. I use 9 ml of A + 9 ml of B in a gallon of water. It’s great for houseplants at that ratio too. So happy someone recommended it to me! Read more

★★★★★

Great start!

Cedric E DarrettFebruary 24, 2026✓ Verified purchase

The nutrients got my plants off to a great start and they’re thriving. Read more

★★★★★

Came in great shape works as labeled

JoshDecember 23, 2025✓ Verified purchase

I’ve been using these for my “tomato’s” and honestly works great makes your plant grow like crazy if it’s your first time maybe try there stater kit Read more

★★★☆☆

Wants you to buy additional products.

jeff andersonJuly 15, 2023✓ Verified purchase

This stuff probably works great. Nothing noticeable after only a week. I have high hopes. I won't be buying anything more from this company because they suggest buying an additional product for it to work well. This was never mentioned in the information on the product description. I feel a little scammed, I would have bought it if it would have been mentioned. I bought this just for my regular garden veggies, I will write a glowing review if my garden does better than normal. A couple of months later and my garden has done the best it ever has, still won't buy it again because of the shady sales tactics. Read more

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