

🌱 Grow smarter, not harder — Jack’s Classic fuels your green empire!
Jack's Classic Nutrients Hydroponic 5-12-26 Part A is a professional-grade, water-soluble powdered fertilizer designed for hydroponic systems. Featuring a precise 5-12-26 NPK ratio with added micronutrients, it ensures optimal plant health and growth without extra feeding. The 25-pound bulk pack offers exceptional value and longevity, making it ideal for both hobbyists and serious growers seeking consistent, high-quality results.










| 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 |
O**.
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.
E**E
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!!!!
L**R
Super Feeds spring plants
Getting plants are flowers ready for spring. The jacks is the perfect starting food.
J**Y
All I’ve used for years.
I’ve used the Jacks 321 formula for years. Simple and reliable. Makes my autoflower plants look like photos. They grow great!
T**R
I love Jacks and you will too
This is my go-to Part A fertilizer, even for hydroponics. Dry fertilizers are always a better value than the liquid in a bottle counterpart, and give you more control over your mix. Make sure to get the Part B and C fertilizers to maximize the potential of the fertilizer, and to find out what amount you need for your specific usage. The price tends to fluctuate a lot, and ends up being over $100 in the Summer, so it may be worth stocking up in the Winter when people are using fertilizers less. Even if the price is around $100 however, you're still going to be saving so much money compared to the alternatives.
L**S
Got what it was
Had holes nutrient spilling out and box was beat up by Mike Tyson
T**H
Jacks=great results cheep
Least expensive, for great results
M**S
Can't say if it's the best
But since I've used it for so long I know the best mix that my garden likes. I don't use it for hydro, but for an outdoor garden and tweak the calcium nitrate to where each group likes and add extra nutrients for other plants that require it. This big bag will last me a few years since the garden isn't huge. Gotta vac seal the unused portion to keep it from absorbing moisture or the water will ruin the measurements.
Trustpilot
Hace 1 semana
Hace 4 días