Power to the Plants
Silica and microbial inputs that unlock real results—stronger structure, faster rooting, bigger blooms.
From Grower roots to global reach
PowerSi was born in the grow room. Founded by professional cultivator Rex Gill in 2016, our mission has always been simple: give plants exactly what they need, nothing they don’t. Our products are clean, proven, and built for serious growers.
Our Products
Silica-Based Additives
Silica builds strength, buffers salt, and drives clean nutrient movement throughout the plant. Our silica inputs improve structure, reduce stress, and enhance performance.
PowerSi Original
- Thick stalks, better uptake
- Use: VEG AND FOLIAR IN EARLY BLOOM
PowerSi Bloom
- Uniform flower stacking,
silica-enhanced delivery - Use: Pre-flower through late bloom
PowerSi Granular
- Slow-release support for soil & outdoor grows
- Use: Top-dress, all stages
Microbial-Based Additives
Our microbes activate phosphorus and potassium, boost root colonization, and revive dead or sterile media for consistent root zone health and flower quality.
PowerSi PK Synergy
- Microbial P/K unlocker for bloom
- Use: all flower
PowerSi Start
- Root growth + transplant success
- Use: Clones, seedlings, transplants
Top Grower Favorites
Why Growers Choose PowerSi?
Stronger
Plants
Silica makes it through the stem, not just the label
Bigger
Yields
Microbes and minerals that make the most of bloom
Cleaner
Feeding
Less salt, better media balance, no clogging
real problems, real solutions
Weak Stems?
Use PowerSi Original or Granular
poor bloom
development?
use powersi bloom + pk synergy
transplant shock?
use powersi start
Sterile Soil?
use powersi pk synergy + Start
works in
any grow
soil
coco
aero
All PowerSi products are compatible with your system and feed program—soluble, consistent, and easy to integrate.
hydro
outdoor
dial in your feed
Get precision results with our official feed charts. Whether you’re running drain-to-waste or a multi-part stock tank system, PowerSi plays well with your base nutrients.
GROWER REVIEWS
Real Reviews From Real Customers
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“PowerSi made everything sturdier. We see the difference in every run.”– Anonymous Review
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“Start gave our clones a head start—roots were out of the cube in days.”– Anonymous Review
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“PK Synergy pushed our terpene profile and weight in the final weeks.”– Anonymous Review
Watch PowerSi in Action
get powersi at growgen
Available at 30+ locations nationwide and online. Talk to a GrowGen rep about the full PowerSi system.