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Humboldts Secret Tree Trunk | Potassium Silicate Additive | Liquid Fertilizer for Thicker Stalks, Stress Resistance & Branch Development | Indoor & Outdoor Plant Food, Hydroponic Nutrients, 32 Ounce

  • Based on 749 reviews
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Availability: Only 3 left in stock, order soon!
Fulfilled by Amazon

Arrives Wednesday, Apr 29
Order within 8 hours and 29 minutes
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Size: 32 Ounce


Features

  • Packaging Update: You may receive previous or updated packaging during our transition. Same formula, same performance. Plant Strength & Stability - Humboldts Secret Tree Trunk is a premium silicate additive that fortifies plant cell walls, producing thicker stalks and stronger branches. By supporting heavier flowers and fruit, it enhances stability, improves overall plant health, and helps maximize yield potential in any growing environment.
  • Enhanced Growth Performance: This silica for plants provides advanced nutrients that improve stem structure and boost resilience. By strengthening natural growth processes, it helps indoor and outdoor plants thrive in soil, coco, or hydroponic systems while delivering vigorous, healthy development across every growth stage.
  • Thicker Stalks & Better Branching: Tree Trunk liquid fertilizer supports stronger nutrient uptake, encouraging sturdy stalks and abundant branch development. This results in improved architecture, better nutrient flow, and increased capacity to support heavy flowers and fruits through both vegetative and flowering cycles.
  • Trusted by Gardeners Everywhere: Humboldts Secret Nutrients are made in the USA with premium-quality ingredients trusted by hundreds of thousands of gardeners. Known for delivering consistent, reliable results, this formula strengthens plants, promotes stable yields, and ensures lasting performance in both indoor and outdoor gardens.
  • Versatile & Easy to Use: Derived from potassium silicate, this liquid silica for plants is compatible with all grow mediums including soil, coco, and hydroponics. Simply apply 2.55 ml per gallon (5 ml 1 teaspoon) with every or every other watering to boost plant strength throughout the entire grow cycle.

Brand: Humboldts Secret


Item Weight: 32 Ounces


Item Form: Liquid


Liquid Volume: 32 Fluid Ounces


Specific Uses For Product: Hydroponic,Plant Food


Brand Name: Humboldts Secret


Model Number: Secret Tree


Global Trade Identification Number: 44


Manufacturer: Humboldts Secret


UPC: 706199757144


Unit Count: 32.0 Ounce


Item Weight: 32 Ounces


Liquid Volume: 32 Fluid Ounces


Item Form: Liquid


Coverage: Medium


Specific Uses For Product: Hydroponic,Plant Food


Target Species: plants


Mixing Ratio: 12.5ml


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Wednesday, Apr 29

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
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  • Afterpay Financing
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  • Financing through Apple Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Top Amazon Reviews


  • WORKS VERY WELL
Size: 32 Ounce
Helps my house plants grow strong!
Reviewed in the United States on December 3, 2024 by joseph

  • Great 👍
Size: 32 Ounce
Great 👍
Reviewed in the United States on November 23, 2024 by Heather Mcnulty

  • It's silica for plants
Size: 1 Gallon
I've switched to mostly Humboldt. Overall, happy and very good results. Thick strong trunk and branches.
Reviewed in the United States on June 24, 2023 by Steven W. Kelley

  • Works
Size: 32 Ounce
Works great , easy to use and it's a good size for the price
Reviewed in the United States on July 27, 2024 by kyle

  • Extra stiff (Pause) branches and stalks
Size: 32 Ounce
One of the best silica supplements I ever purchased
Reviewed in the United States on May 21, 2024 by Jon P.

  • Does what it says
Size: 8 Ounce
Game changer
Reviewed in the United States on September 8, 2024 by Lisa Jacobus

  • Does it work?
Size: 32 Ounce
I don't see any difference.
Reviewed in the United States on October 2, 2023 by Pirate face

  • I lost 6 trees due to heat stress last summer. Hope to do better this year
Size: 32 Ounce
We have been experiencing unusually hot, dry summers in our zone 8 growing area. We experienced 50 days of 100+ temperatures that killed 6 new trees. I have been using this product to help the replacements to survive the heat this year.
Reviewed in the United States on April 29, 2024 by Mitch Miller

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