Humboldts Secret Flower Stacker | 0-7-5 Bloom Booster with Vitamin B1 | High Phosphorus Potassium Flowering Nutrients | Potting Soil Hydroponics Coco | Indoor & Outdoor Plants | 8 Ounce
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Availability:
In Stock.
Arrives
Monday, Mar 23
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Size: 8 Ounce
Features
- Packaging Update: You may receive previous or updated packaging during our transition. Same formula, same performance. Bigger Denser Harvests - Our humboldts secret flower stacker 0 7 5 bloom additive helps plants increase yields by up to 30%, building tighter nodes and denser flower sites on indoor and outdoor plants in potting soil for standout aroma, rich color, and reliable bag appeal across every cycle.
- Peak Bloom Nutrition: This concentrated flowering fertilizer delivers high phosphorus and potassium exactly during the bloom window to drive rapid bud formation, fuller calyx stacking, and enhanced resin and essential oils while supporting efficient nutrient uptake and balanced plant metabolism.
- Simple Clean Application: Begin in week 3 of flower and use with every or every other watering; this dependable flower booster mixes fast, stays pH stable, and runs clean in soil, coco, hydroponics, and aquaponics, preventing buildup, line clogging, and downtime so your schedule stays consistent.
- Stronger Stress Resilience: Our balanced flowering nutrients include Vitamin B1 to support transplant recovery, early establishment, and overall vigor, helping plants handle training, heat, and light intensity swings with confidence for a fuller, more uniform canopy from top to bottom.
- Flexible Dosing And Compatibility: Designed to pair seamlessly with humboldt secret nutrients, the 8 ounce bottle mixes approximately 45 to 230 gallons depending on dilution, giving precise control for any plant count and grow method while preserving clean reservoirs and predictable results.
Brand: Humboldts Secret
Item Weight: 8 Ounces
Item Form: Powder
Liquid Volume: 8 Fluid Ounces
Specific Uses For Product: Hydroponic,Plant Food,Potting
Brand: Humboldts Secret
Item Weight: 8 Ounces
Item Form: Powder
Liquid Volume: 8 Fluid Ounces
Specific Uses For Product: Hydroponic,Plant Food,Potting
Manufacturer: Humboldts Secret
UPC: 089902782573
Unit Count: 8.0 Ounce
Product Dimensions: 2 x 2 x 7 inches
Item Weight: 8 ounces
Item model number: 4316245903
Is Discontinued By Manufacturer: No
Frequently asked questions
If you place your order now, the estimated arrival date for this product is:
Monday, Mar 23
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.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
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Similar Products
Top Amazon Reviews
Size: 8 Ounce
This Bloom Booster with Vitamin B1 is fantastic! It’s helped my plants produce stronger blooms and healthier foliage—everything looks more vibrant and lush. The added Vitamin B1 seems to reduce transplant shock and supports overall plant vigor, especially when introducing new plants to the garden. It’s easy to mix and apply with my watering routine, and I’ve noticed that flowers stay fuller and more abundant throughout the season. The formula feels high‑quality and effective without being overly complex. If you want a reliable way to promote better flowering and stronger, healthier plants, this bloom booster is an excellent choice. Highly recommend!
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Reviewed in the United States on February 12, 2026 by joseph D Pergolotti
Size: 32 Ounce
I use the whole Humboldt's Secret nutrient line on plants grown indoors in tents with automated lighting, circulation and exhaust fans and manual feeding, watering, temperature and humidity controls. My flowers are cup quality, every time. Top quality nutrients, broad spectrum, easy schedule and dosing and super reasonable compared to other brands with comparable offerings. On average, I'd say my return on investment in yield:nutrient is about 50:1. Hard to argue that. I'm a believer.
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Reviewed in the United States on January 20, 2026 by Jason Gonzalez
Size: 32 Ounce
I use all of the Humboldt products and they were absolutely perfect. My plants are doing great if you follow the instructions. Thank you.
Reviewed in the United States on January 19, 2026 by captkirk
Size: 8 Ounce
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.
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Reviewed in the United States on January 1, 2021 by kenneth williams kenneth williams
Size: 32 Ounce
I haven’t used it yet, but what I’ve heard and read about this product. It works awesome I’m gonna find out that’s for sure.
Reviewed in the United States on February 8, 2026 by brian kress
Size: 32 Ounce
Its a really good product...My plants flowered beautiful
Reviewed in the United States on January 20, 2026 by Anahi
Size: 8 Ounce
rock resonator 4 times better
Reviewed in the United States on September 8, 2025 by JERRY
Size: 32 Ounce
Seem to really help the flowering cycle.
Reviewed in the United States on March 3, 2026 by MICHAEL MURGO