---
product_id: 67861012
title: "Jack's Classic Nutrients Hydroponic 5-12-26 Professional Fertilizer Part A, 25 lbs"
brand: "jack's classic"
price: "€ 369.33"
currency: EUR
in_stock: true
reviews_count: 8
category: "Jack's Classic"
url: https://www.desertcart.gr/products/67861012-jacks-classic-nutrients-hydroponic-5-12-26-professional-fertilizer-part
store_origin: GR
region: Greece
---

# Micronutrients for optimal plant health Water-soluble powder for easy mixing 5-12-26 precise nutrient ratio Jack's Classic Nutrients Hydroponic 5-12-26 Professional Fertilizer Part A, 25 lbs

**Brand:** jack's classic
**Price:** € 369.33
**Availability:** ✅ In Stock

## Summary

> 🌿 Feed like a pro, grow like a legend!

## Quick Answers

- **What is this?** Jack's Classic Nutrients Hydroponic 5-12-26 Professional Fertilizer Part A, 25 lbs by jack's classic
- **How much does it cost?** € 369.33 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.gr](https://www.desertcart.gr/products/67861012-jacks-classic-nutrients-hydroponic-5-12-26-professional-fertilizer-part)

## Best For

- jack's classic enthusiasts

## Why This Product

- Trusted jack's classic brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Hydroponic-Ready:** Designed specifically for hydroponic systems with clear mixing ratios to optimize continuous liquid feeding.
- • **Effortless Mixing:** Water-soluble powder lets you create gallons of potent fertilizer with minimal effort—maximize every gram.
- • **Cost-Effective Bulk Size:** 25 lbs of premium fertilizer delivers long-lasting value for serious growers and hobbyists alike.
- • **Precision Nutrient Balance:** Tailored 5-12-26 formula fuels vigorous growth across diverse crops and environments.
- • **All-in-One Micronutrient Boost:** No extra feeding needed—micronutrients included for robust, healthy plants from seedling to harvest.

## Overview

Jack's Classic Nutrients Hydroponic 5-12-26 is a professional-grade, water-soluble powdered fertilizer designed for hydroponic systems. Its precise nutrient ratio combined with essential micronutrients supports optimal plant growth and health without additional feeding. The 25 lb bulk size offers exceptional value for both hobbyists and serious growers, ensuring consistent, high-quality yields.

## Description

desertcart.com : Jack's Classic Nutrients Hydroponic 5-12-26 Professional Fertilizer Part A, 25 lbs : Patio, Lawn & Garden

Review: Jacks is the best! Price and quality you just can't beat. - Jack's is all you need to grow great crops. I doing Jacks 321 in dwc in RO water.. Part A, Epsom Salt, and Cal-Nit. This stuff works so well that I bought big 25lbs bags. For about $200 bucks I have enough nutes that will last a small/hobby grower, like myself, many years. I only run about 800ppm max in flower and I run at least a 7 day flush of ph adjust RO water before harvest. I have no issues starting seedlings and clones directly in 300ppm of 3,2,1. I do add ph up powder to the mix to get it up to 6.0ph since I use RO water.
Review: Best fertilizer on the market - I use this for my hydroponic grows, and this is like giving your plants steroids!!! It’s an old school fertilizer, but it has got to be the most effective fertilizer on the market!!! If you follow the instructions, your plants will grow so fast, and produce like nothing you have ever used before!!! There is nothing better simply put!!!!

## Features

- 5-12-26 Analysis - Supplies a specific balance of macro, secondary, and micronutrients for many different growing environments and crop types.
- Water-Soluble Powder – Powdered concentrates go further than liquid fertilizers. Simply mix your measured powder with water and you are ready to feed with multiple gallons of liquid fertilizer!
- Mixing Rate – Proper mixing ratios are supplied on the bag for optimal feeding.
- Micronutrients - Added micronutrients supply your plant with the nutrition it needs for optimal growth and health. Unlike other fertilizers, additional feeding is not required.
- Continuous Liquid Feed Program – Intended for use with hydroponic systems. Mixing instructions by volume included.

## Technical Specifications

| Specification | Value |
|---------------|-------|
| Best Sellers Rank | #54,948 in Patio, Lawn & Garden ( See Top 100 in Patio, Lawn & Garden ) #1,388 in Garden Fertilizers |
| Brand | Jack's Classic |
| Customer Reviews | 4.8 out of 5 stars 386 Reviews |
| Item Form | Powder |
| Item Weight | 25 Pounds |
| Liquid Volume | 500 Milliliters |
| Manufacturer | JR Peters |
| Specific Uses For Product | Hydroponic |

## Product Details

- **Brand:** Jack's Classic
- **Item Form:** Powder
- **Item Weight:** 25 Pounds
- **Liquid Volume:** 500 Milliliters
- **Specific Uses For Product:** Hydroponic

## Images

![Jack's Classic Nutrients Hydroponic 5-12-26 Professional Fertilizer Part A, 25 lbs - Image 1](https://m.media-amazon.com/images/I/71tIae-eNvL.jpg)

## Questions & Answers

**Q: Is this product water soluable**
A: Yes it is. It is very soluable. 

I reccomended running it at these ragione.

Part A : 3g/gallon
Part B : 2g/ gallon
Epsom Salt: 1g/gallon 

And if you are using RO water, add 5ml/gallon Calimagic to this mix.  It works fangastic.

**Q: Are they organic?**
A: No

**Q: Do I need to add something to this if I am growing tomatoes (kratky method of hydroponics)?**
A: Yes, calcium nitrate must be dissolved separately. It is also called Jack's part B, or 15-0-0 (Ca-19%), use a greenhouse brand like jacks, Powergrow, or Yara. I have found the super cheap brands (eg southernAG, highYield) may be coated with insoluble goop, or otherwise contaminated.
The two parts must be diluted before mixing or the calcium and sulfur will form gypsum and gypsum is only mildly soluble so can settle out of a concentrate and is then very hard to redissolve.

**Q: can it be used in soil? If so at what rate?**
A: Absolutely...same rate as hydro is fine. If your using it for canna I increase slowly and like keeping it under 1000ppm cus I use dry amendments as well. Jack's also has a line of boosters

## Customer Reviews

### ⭐⭐⭐⭐⭐ Jacks is the best! Price and quality you just can't beat.
*by O***. on August 3, 2024*

Jack's is all you need to grow great crops. I doing Jacks 321 in dwc in RO water.. Part A, Epsom Salt, and Cal-Nit. This stuff works so well that I bought big 25lbs bags. For about $200 bucks I have enough nutes that will last a small/hobby grower, like myself, many years. I only run about 800ppm max in flower and I run at least a 7 day flush of ph adjust RO water before harvest. I have no issues starting seedlings and clones directly in 300ppm of 3,2,1. I do add ph up powder to the mix to get it up to 6.0ph since I use RO water.

### ⭐⭐⭐⭐⭐ Best fertilizer on the market
*by E***E on January 27, 2026*

I use this for my hydroponic grows, and this is like giving your plants steroids!!! It’s an old school fertilizer, but it has got to be the most effective fertilizer on the market!!! If you follow the instructions, your plants will grow so fast, and produce like nothing you have ever used before!!! There is nothing better simply put!!!!

### ⭐⭐⭐⭐⭐ Super Feeds spring plants
*by L***R on March 27, 2024*

Getting plants are flowers ready for spring. The jacks is the perfect starting food.

## Frequently Bought Together

- Jack's Classic Nutrients Hydroponic 5-12-26 Professional Fertilizer Part A, 25 lbs
- Jack's Classic Nutrients 15-0-0 Part B Water-Soluble Fertilizer for Calcium Uptake and Strong Leaf Growth in Continuous Liquid Feed Programs, 25Lbs

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*Product available on Desertcart Greece*
*Store origin: GR*
*Last updated: 2026-02-04*