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 - 5 Gallons

    • Based on 2,514 reviews
Condition: New
Checking for product changes
$425.00 Why this price?

Buy Now, Pay Later

As low as / mo
  • – Up to 36-month term with PayTomorrow
  • – 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: Only 4 left in stock, order soon!
Fulfilled by Amazon
Arrives Monday, Nov 25
Order within 2 hours and 4 minutes
Available payment plans shown during checkout

Size: 5 Gallon


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


Coverage: 30


Liquid Volume: 5 Gallons


Specific Uses For Product: Hydroponic,Plant Food


Package Dimensions: 15.2 x 14 x 9.5 inches


Item Weight: 49.9 pounds


Manufacturer: HS Supplies LLC


Is Discontinued By Manufacturer: No


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Monday, Nov 25

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

    • It works!!!
Size: 8 Ounce
Review Image by Corey Corey
If you want dense nugs use this for 6 outta 10 weeks of flower.(wk 1,2,3,4,5,6) then flush with water till runs clean. Works great with foxfarm grow big and bloom. Get your plants use to it with small amounts then add as much as you can 😂😂😂 just watch for leave burning. Really a great product. I would love to run a grown with all Humboldt's secret products. Hmu for product testing. ... show more
Reviewed in the United States on January 30, 2024 by Corey Corey
    • Fertilizer
Size: 32 Ounce
Seems to be good stuff and will probably buy again..
Reviewed in the United States on February 23, 2024 by Charles G.
    • 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
    • Wow
Size: 8 Ounce
This was my first time using nutrients in my garden, I had a pretty great turn out of tomatoes last year. It’s easy to use, crop tastes amazing, and it’s worth the money.
Reviewed in the United States on March 2, 2024 by Shay
    • This stuff works
Size: 8 Ounce
It maybe early but it seems to make really stout thick flowers. It makes rose buds gigantic when applied right. I can only imagine what it does for other flowers. So far so great. I’m impressed in such a short amount of time that it can do this but it’s hard to tell if it’s this or the cal mag or silica or a combination of all. Good stuff if it doesn’t kill your plants and it doesn’t . ... show more
Reviewed in the United States on March 9, 2024 by The Architect
    • It stacks them
Size: 32 Ounce
Review Image by Daniel Thornburg Daniel Thornburg
Review Image by Daniel Thornburg Daniel Thornburg
Review Image by Daniel Thornburg Daniel Thornburg
Review Image by Daniel Thornburg Daniel Thornburg
Review Image by Daniel Thornburg Daniel Thornburg
Love it
Reviewed in the United States on January 11, 2024 by Daniel Thornburg Daniel Thornburg
    • Additive's Impact: Instinct Points to Noticeable Difference
Size: 8 Ounce
Though the absence of Part A and Part B is often evident in leaf discoloration, it can be challenging to definitively attribute the effects to this additive. However, drawing from my extensive experience with numerous growing cycles, my intuition strongly suggests that this additive is indeed making a noticeable impact. ... show more
Reviewed in the United States on November 9, 2023 by Everyons Uncle Ed
    • Not easy to use
Size: 32 Ounce
The product arrived without a tool to measure litter, so I have no idea how much to use each time without a measuring tool
Reviewed in the United States on November 23, 2023 by shirley

Can't find a product?

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