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Humboldts Secret

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

    • Based on 2,633 reviews
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Availability: In Stock.
Fulfilled by Amazon
Arrives Monday, May 5
Order within 1 hour and 30 minutes
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Size: 32 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 Weight: 32 Ounces


Item Form: Liquid


Coverage: 30


Liquid Volume: 128 Fluid Ounces


Brand: Humboldts Secret


Item Weight: 32 Ounces


Item Form: Liquid


Coverage: 30


Liquid Volume: 128 Fluid Ounces


Specific Uses For Product: Hydroponic,Plant Food


Target Species: Plants


Manufacturer: Humboldts Secret


UPC: 089902782559


Unit Count: 32 Fluid Ounces


Package Dimensions: 7.44 x 5.2 x 2.28 inches


Item Weight: 2 pounds


Is Discontinued By Manufacturer: No


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Monday, May 5

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.

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Top Amazon Reviews

    • Great product!
Size: 8 Ounce
Great supplement for your buds!
Reviewed in the United States on February 9, 2025 by Bobby L.
    • Great results
Size: 32 Ounce
Will use again
Reviewed in the United States on February 6, 2025 by Milton b hartung
    • 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
    • Humboldts secret flower stacker is worth every penny
Size: 32 Ounce
My lemon tree growth rate increased tremendously when I added Humboldts secret flower stacker to my current nutrients & the health of my lemon tree increased in a matter of days it’s functionality is like no other
Reviewed in the United States on March 5, 2025 by Kenneth L.
    • Humboldts Secret Flower Stacker
Size: 8 Ounce
Humboldts Secret Flower Stacker is an amazing product for anyone looking to enhance their plant’s flowering stage. After using it on my indoor and outdoor plants, I noticed bigger, healthier blooms within a short time. It's easy to use, and the concentrated formula goes a long way. My plants have never looked better, and I’ve seen an increase in yield. A must-have for gardeners seeking more abundant harvests! ... show more
Reviewed in the United States on October 10, 2024 by Verified Amazon User
    • Great product
Size: 8 Ounce
It shows signs of working within two days after first use.
Reviewed in the United States on January 14, 2025 by Todd W.
    • Worked Well
Size: 32 Ounce
Review Image by LindaBJohnson LindaBJohnson
Cannabis plants in tower garden (hydro/aeroponic) were not progressing at the end of the grow period until we used this (possibly due to reduced sun exposure). Flower Stacker did improve the buds! Much happier with the crop than we expected to be.
Reviewed in the United States on November 25, 2024 by LindaBJohnson LindaBJohnson
    • super concentrate
Size: 32 Ounce
Haven't used yet am looking forward to. Directions on container to small to read with 150 readers and magnify glass. My spouse with progressive lens glasses and magnifier thinks she read correctly. Having to convert ml to ounces normally not an issue however having to measure a 1/4 tsp. for a gallon wasn't easy pouring from a .924 liter container to a teaspoon. I guess I could have spent the day looking for a 1/4" tsp. Nevertheless explicit warnings of accurate. measurement, timing of 3 weeks after flower bloom, to apply 1st dose is scary with all the warnings about plant burn out. We'll see how it goes. ... show more
Reviewed in the United States on November 20, 2024 by Namrto

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