Search  for anything...
Humboldts Secret

Humboldts Secret Flower Stacker – Best Flowering Formula for Bigger Harvests - Flowering Plant Food – Nutrient System for Potting Soil for Indoor & Outdoor Plants – 1 Gallon

    • Based on 2,323 reviews
Condition: New
Checking for product changes
$99.98 Why this price?
Save $25.01 was $124.99

Buy Now, Pay Later

As low as $16.66 / mo
  • – 6-month term
  • – No impact on credit
  • – Instant approval decision
  • – Secure and straightforward checkout

Ready to go? Add this product to your cart and select a plan during checkout. Payment plans are offered through our trusted finance partners Klarna, PayTomorrow, Affirm, Afterpay, Apple Pay, and PayPal. No-credit-needed leasing options through Acima may also be available at checkout.

Learn more about financing & leasing here.

Selected Option

Free shipping on this product

This item is eligible for return within 30 days of receipt

To qualify for a full refund, items must be returned in their original, unused condition. If an item is returned in a used, damaged, or materially different state, you may be granted a partial refund.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

Availability: In Stock.
Fulfilled by Amazon
Arrives Saturday, Nov 30
Order within 19 hours and 53 minutes
Available payment plans shown during checkout

Size: 128 Ounce


Features

  • INCREASE YIELDS BY UP TO 30%: Flower Stacker is a flowering additive designed to help your plants natural ability to increase yield and flower density. Its an ideal nutrient solution for potting soil for indoor plants and outdoor plants.
  • PREMIUM INGREDIENTS: Our Humboldts Secret Flower Stacker is made with quality ingredients to ensure the development of your flowers. Perfectly suited for potting soil for indoor plants!
  • CONTAINS VITAMIN B1: Vitamin B1 has been touted as a cure-all for transplant shock. Labels typically claim that B1 supports conditions for better plant establishment and growth in a wide range of plants.
  • HIGH AMOUNTS OF PHOSPHORUS AND POTASSIUM: Application of phosphorus and potassium during the flower development phase improves soil/foliar nutrient conditions for better crop yields.
  • ADDED FLOWERING AGENT TO YOUR REGIME: Flowering boosters are particularly important in hydroponic and agricultural industries. Thousands of growers use Flower Stacker as an additional flowering agent to maximize their yields by harnessing the power of our clean-running formula.

Brand: Humboldts Secret


Item Form: Liquid


Liquid Volume: 1 Gallons


Specific Uses For Product: Hydroponic,Plant Food


Package Dimensions: 11.38 x 6.89 x 4.45 inches


Item Weight: 9.17 pounds


Manufacturer: Humboldts Secret


Is Discontinued By Manufacturer: No


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Saturday, Nov 30

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

  • Klarna Financing
  • Affirm Pay in 4
  • Affirm Financing
  • Afterpay Financing
  • PayTomorrow Financing
  • Financing through Apple Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Similar Products

Top Amazon Reviews

    • Increases flower blooms
Size: 32 Ounce
Have used this for two years. Noticeable increase of blooms almost immediately. A little goes a long way as it is diluted with water for us. Best price I have ever found.
Reviewed in the United States 🇺🇸 on May 28, 2023 by Diane Prange
    • Humboldt Sweet and Sticky and Stacker work really well together.
Size: 8 Ounce
Review Image by kenneth williams kenneth williams
Review Image by kenneth williams kenneth williams
Review Image by kenneth williams kenneth williams
Review Image by kenneth williams kenneth williams
The media could not be loaded. Daddy like! How is this evening happening? These pictures were taken January 1,2021 and according to my wife are about 11 weeks old. For the last three or four weeks the daytime high temperature has 68°. And at night of about 45° . And the plants seem to love it. Look how tight the bud blossoms are, it’s like one big forearm. I will bring it in soon put it under my grow lights and see how it likes that environment. The temperature is a low of about 65°F, and a high of 75°F. It’s flowing season here with 12 hour days similar to what the bud was getting outdoors. I will use flowers shield Humboldt flower shield to get any pest or mites or anything that might be on it off of it before I bring it inside grow room Also in the garden we have passion fruit that is 35’ long by 12’ wide. It took over a clothes line and outdoor clothes away but I put number 10 copper wire honored to support the passion fruit tree. We have a minature orange trees to produces grap fruit sized oranges when it wants to. The lime trees love the sweet and sticky as well. I want to see how good they’re going to taste. Ever fruit tree loves Miracle grow to grow foliage nice and green the fruit as well but that was in the summer. should’ve taken a picture of it I have a lot of little baby lemons and I limes. Once the flowers turn into small fruit the trees get Humboldt stacker. We harvest passion fruit pretty much every few days for a couple of months or longer. I forgot I started with a 4 ounce bottle of the stacker and sweet and sticky by Humboldt. For my cannabis plant growing indoors just a couple of plants. And I realized I started buying the larger bottles because it makes our fruit trees produce really delicious fruit. It might seem like a lot of money at first but the stuff is very concentrated and it goes along way. Our passion fruit already has blossoms were still using miracle grow. I still have Humboldt stacker and sweet and sticky for this year I’ll probably buy some more because it’s worth it it’s very concentrated. ... show more
Reviewed in the United States 🇺🇸 on January 1, 2021 by kenneth williams kenneth williams
    • Be careful
Size: 8 Ounce
Great product but definitely follow the instructions because it WILL cause nutrient burn if you get aggressive with your dosing.
Reviewed in the United States 🇺🇸 on March 21, 2023 by Mike Kessinger
    • Good flowers stacker
Size: 8 Ounce
Worth the money and very easy to use
Reviewed in the United States 🇺🇸 on March 10, 2023 by James Million
    • Good product
Size: 128 Ounce
I like that you use one product for grow and flower. All you have do, is add flavor product at end
Reviewed in the United States 🇺🇸 on February 10, 2023 by Duffy Gehrts
    • Best harvest in years using the Humboldt line from beginning to finish.
Size: 32 Ounce
Review Image by Bruce Bruce
Review Image by Bruce Bruce
Review Image by Bruce Bruce
Review Image by Bruce Bruce
Review Image by Bruce Bruce
I used the entire line of Humboldt this year except for the Tree Trunk. It is actually a system of several products that are easy to use and mix. Get yourself a 12cc or larger syringe for easy measuring. Nothing burnt this year as has happened in the past with other brands. Giant Gorilla Glue donkey d!#&$ grown in a 2 x 3 tent with a Spiderfarm LED, soil bags using Foxpro Ocean. Outdoors giant Hybrids produced way too much for personal use. Splurge on the nutrients and the payback is 10 fold. ... show more
Reviewed in the United States 🇺🇸 on October 20, 2022 by Bruce Bruce
    • Add less for hydro application
Size: 32 Ounce
Good product.i always use this line and have very good and beautiful results..
Reviewed in the United States 🇺🇸 on January 27, 2023 by Albert G.
    • Not as impressed
Size: 8 Ounce
As I thought I would be. I am a small home-craft gardener, growing no more than 10 plants. So I am very conscious of what I put in my plants and soil. I love to try new things, but this one didn't live up to the hype for me. I noticed that I tended to get nutrient burn much more easily with adding this. I grow in soil/perlite and I mix my nutrients in a bottle. Yes, this stuff can stink when premixed after awhile. I just personally have not noticed any difference in flower stacking and/or bigger buds or heavier yields than when I DON'T use this product, so for me, it is more of a hassle. I would not use again. ... show more
Reviewed in the United States 🇺🇸 on October 20, 2022 by Jackie E.

Can't find a product?

Find it on Amazon first, then paste the link below.