![Lawn Fertilizer with Iron – Dark Venom [3-0-5 + 1.5% Iron]](http://gardeniq.com/cdn/shop/files/Dark_Venom_Spray_Quart.png?v=1776884345&width=900)
GardenIQ — Nutrx™ Technology
Dark Venom [3-0-5 + 1.5% Fe]
High-iron lawn food engineered for deep green, professional results.
Size
$45.00
Quantity
Save $10 + free shipping
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Octane Boost [4-0-2]
Micronutrient complex for accelerated growth
$30.00
Doonbeg [3-0-2]
North Atlantic kelp & molasses — feeds soil microbes
$30.00
Blended in Chicago
Free shipping on bundles
Nutrx™ technology
About this product
The lawn food your neighbors will ask about.
Dark Venom is a high-iron liquid lawn fertilizer built for homeowners who take their lawn seriously. The high iron content drives deep, rich green color fast — without the excessive growth surge that forces you to mow every three days.
Powered by Nutrx™ technology, Dark Venom is formulated for maximum absorption efficiency so your lawn gets more from every application. Less product, better results, and dramatically reduced burn risk compared to granular alternatives.
Available in spray-ready quart and refill quart formats. Pair with Doonbeg or Octane Boost for the complete lawn system.
Powered by Nutrx™ technology, Dark Venom is formulated for maximum absorption efficiency so your lawn gets more from every application. Less product, better results, and dramatically reduced burn risk compared to granular alternatives.
Available in spray-ready quart and refill quart formats. Pair with Doonbeg or Octane Boost for the complete lawn system.
Best for
- Cool and warm season grasses
- Lawns showing yellowing or iron deficiency
- High-traffic lawn areas
- Established lawns needing color improvement
- Pre-season and in-season feeding
Application
Three steps. Real results.
01
Mix or spray
Use the spray quart ready-to-go, or dilute the refill at 1–2 oz per gallon of water.
02
Apply
Apply evenly across your lawn every 2–4 weeks during the growing season. Water in lightly after application.
03
Watch it work
Deep green color typically visible within 5–7 days. Consistent application maintains color and turf health all season.
The science
Why Dark Venom works: Nutrx™ technology
Every GardenIQ formula is powered by Nutrx™ — a proprietary blend of carbon complexes, humic and fulvic acids, protein complexes, and amino acids developed through decades of professional agronomic research. Most fertilizers sit in the soil. Nutrx™ is designed to maximize how much your lawn actually absorbs — so you see more results with less product, and dramatically reduced burn risk.
Learn the science behind Nutrx™ →
Customer reviews
What Dark Venom customers are saying
Guaranteed Analysis
What's Inside
| Total Nitrogen (N) | 3.0% |
| Nitrate Nitrogen | 1.56% |
| Urea Nitrogen | 1.44% |
| Soluble Potash (K₂O) | 5.0% |
| Total Iron (Fe) | 1.50% |
Derived From
Potassium Nitrate, Urea, & Ferrous Sulfate