Premium vegetative growth formula for our complete 4-part hydroponic system. Higher potassium than typical liquid grow formulas promotes thicker stems and denser canopy development — at 50–70% lower cost than liquid alternatives.
Double the nitrogen and higher potassium than typical 2-1-6 liquid grow formulas, promoting faster vegetative growth and stronger stem development from the first week of use.
The elevated 6% potassium level builds thicker cell walls and denser canopy structure, supporting heavy fruit loads and reducing the risk of stem breakage at peak production.
Focused NPK-only composition allows precise customization of micronutrient delivery through Micro Green, giving you full control over nutrition at each growth stage.
Dissolves completely with no residue, keeping drip emitters, NFT channels, and aeroponics nozzles clear. Compatible with DWC, ebb & flow, coco coir, and soil applications.
Registered with the California Department of Food and Agriculture and independently tested for heavy metal content, ensuring consistent purity batch after batch.
Concentrated powder means you pay for nutrients, not water and plastic. One 1.7 lb package makes a full gallon of stock solution that treats up to 100 gallons of reservoir.
Dry powder format never separates, degrades, or precipitates in the container. Sealed stock solutions remain stable for 6+ months — no more throwing away expired liquid bottles.
Powder ships at a fraction of the weight of equivalent liquid nutrients, dramatically reducing your carbon footprint per nutrient unit delivered and cutting packaging waste.
Engineered to work in precise balance with Cal-Mag Plus 2-0-0, Micro Green 2-0-3, and Blossom Green 2-6-8 — a complete system covering every growth stage from clone to harvest.
The same formula trusted by commercial greenhouse and hydroponic operations for decades, now available to home growers in sizes from 1.7 lbs to 17 lbs.
Grow Green 4-2-6 is manufactured from pharmaceutical and agricultural-grade mineral salts selected for rapid dissolution, maximum solubility, and consistent nutrient availability across all pH ranges used in hydroponics.
Primary source of both nitrogen and potassium. Provides nitrate-N for direct plant uptake and high-solubility K without adding chloride or sodium.
Delivers soluble phosphorus for energy transfer (ATP) and root development, plus additional potassium — completely chloride-free and safe for sensitive crops.
Supplemental potassium with sulfur for a complete macronutrient profile. Preferred over potassium chloride for hydroponic systems where chloride accumulation is a concern.
Supplies background magnesium and sulfur to support chlorophyll synthesis and enzyme activity throughout the vegetative stage.
Most liquid "grow" formulas use a 2-1-6 ratio optimized for minimal input cost. Grow Green doubles the nitrogen and maintains a high-potassium profile to match the actual demand of fast-growing vegetative crops — the plants take up more N and K during this phase than any standard formula delivers.
Nitrate nitrogen drives chlorophyll synthesis, amino acid production, and rapid cell division. At 4%, Grow Green delivers twice the nitrogen of typical 2-1-6 formulas, meaning you can achieve the same target ppm-N using less product — or push growth rates harder at the same dose.
Provides sufficient phosphorus for energy transfer (ATP), root development, and vegetative cell function without overloading the formula. High-P grow formulas can limit potassium uptake through antagonism — the 2% level avoids this while preparing plants for the flowering transition.
Potassium governs stomatal regulation, water transport, and cell wall integrity. The elevated 6% K level supports thicker stems, improved stress tolerance, and the structural development that directly determines how much fruit weight a plant can support at harvest.
Because Grow Green's N concentration is double that of 2-1-6 formulas, you use significantly less product to hit your target EC — compounding the cost savings beyond the liquid-to-powder conversion alone.
Grow Green contains only macronutrients. Keeping micros in a separate product (Micro Green) prevents pH-driven precipitation and chelation competition that occurs when iron, calcium, and phosphorus share the same bottle.
Formulated from refined mineral salts rather than mined raw materials, Grow Green delivers consistent elemental ratios batch to batch with no organic load that could alter solution pH or promote microbial growth in reservoirs.
Each component contributes a known, consistent EC value to the reservoir. This makes dialing in target electrical conductivity straightforward — no batch variation that shifts your ppm targets week to week.
Results vary with crop type, water quality, temperature, and system type. Monitor EC and pH daily during peak veg for best outcomes.
See how Greenway Biotech's powder concentrate stacks up against popular liquid nutrient systems.
| Feature | Greenway Biotech 4-Part | General Hydroponics Flora Series | Advanced Nutrients pH Perfect |
|---|---|---|---|
| Format | Concentrated Powder | Pre-mixed Liquid | Pre-mixed Liquid |
| Cost per Gallon | ~$0.25/gallon | ~$0.75–1.00/gallon | ~$1.00–1.50/gallon |
| Shelf Life | Indefinite (dry powder) | 1–2 years (liquid) | 1–2 years (liquid) |
| Shipping Weight | ~7 lbs (full system) | ~25+ lbs (gallon trio) | ~25+ lbs (gallon trio) |
| Heavy Metal Testing | ✅ Third-party tested | Not specified | Not specified |
| CDFA Registered | ✅ Yes | Varies by state | Varies by state |
| Cal-Mag Included | ✅ Included in system | ❌ Extra purchase (CALiMAGic) | ❌ Extra purchase (Sensi Cal-Mag) |
| Made in USA | ✅ California | ✅ USA | ❌ Canada |
| Annual Savings (100 gal/week) | $2,600–3,900/year | Baseline | Higher than GH |
Mix the entire package at once to ensure uniform concentration. Use warm water (65–75°F) for faster dissolution. Store in a cool, dark place and shake before each use.
| Product | Powder → Water | Stock Yield | Shelf Life |
|---|---|---|---|
| Cal-Mag Plus 2-0-0 | 2.5 lbs → 1 gallon | 1 gallon concentrate | 6+ months |
| Grow Green 4-2-6 | 1.7 lbs → 1 gallon | 1 gallon concentrate | 6+ months |
| Micro Green 2-0-3 | 1.5 lbs → 1 gallon | 1 gallon concentrate | 6+ months |
| Blossom Green 2-6-8 | 1.8 lbs → 1 gallon | 1 gallon concentrate | 6+ months |
| Package Size | Water Needed | Stock Solution Yield |
|---|---|---|
| 1.7 lbs | 1 gallon | 1 gallon concentrate |
| 3.4 lbs | 2 gallons | 2 gallons concentrate |
| 8.5 lbs | 5 gallons | 5 gallons concentrate |
| 17 lbs | 10 gallons | 10 gallons concentrate |
| Growth Stage | Cal-Mag Plus | Grow Green | Micro Green | Blossom Green | EC Target |
|---|---|---|---|---|---|
|
Seedlings / Clones Week 1–2 |
2.5 | 1.25 | 1.25 | 1.25 | 0.5–0.8 |
|
Early Vegetative Week 3–4 |
5 | 5 | 5 | 5 | 1.0–1.4 |
|
Late Vegetative Week 5–6 |
7.5 | 15 | 10 | 5 | 1.4–1.8 |
|
Transition Week 7–8 |
10 | 10 | 10 | 10 | 1.6–2.0 |
|
Early Bloom Week 9–10 |
10 | 5 | 10 | 15 | 1.8–2.2 |
|
Peak Bloom Week 11–13 |
10 | 0 | 10 | 20 | 2.0–2.5 |
|
Late Bloom / Flush Week 14+ |
5 | 0 | 7.5 | 15 | 1.5–2.0 |
| System Type | Application Method | Special Considerations |
|---|---|---|
| DWC / RDWC | Add to reservoir | Change weekly, monitor pH daily |
| NFT / Aeroponics | Continuous feed | Filter solution, check emitters regularly |
| Ebb & Flow | Flood cycles | Adjust concentration for flood frequency |
| Drip / DTW | Multiple daily feeds | 10–20% runoff recommended |
| Coco / Soilless | Daily feeding | Never let media dry completely |
Don't stop Grow Green abruptly. During weeks 7–8, run both Grow Green and Blossom Green at equal rates (10 ml/gal each) to bridge the transition. This prevents the nitrogen crash that causes yellowing during the stretch phase. Reduce Grow Green to 5 ml/gal in early bloom, then drop to 0 at peak bloom when Blossom Green takes over entirely.
Refer to the Safety Data Sheet (SDS) for complete safety information.
Grow Green works best as part of our complete 4-part hydroponic system. All four components ensure balanced nutrition from seedling to harvest — no guesswork, no missing elements.
Foundation of the system. Provides calcium, magnesium, and chelated iron. Always add FIRST to prevent precipitation. Critical for RO water users and coco coir growers.
Complete 7-element micronutrient blend with chelated minerals. Use throughout ALL growth stages — micronutrients catalyze the uptake of every macro nutrient in this system.
High-phosphorus flowering formula for abundant blossoms and maximum yield. Increase as you taper Grow Green during the transition to bloom in weeks 7–8.
All four products together. Makes 4 gallons of stock solution and treats up to 400 gallons of nutrient solution — the easiest way to get started with the full system.
Yes. Match the ppm-N of your current liquid product using the feeding schedule, and you'll see equal or better results at 50–70% lower cost per finished gallon. Because Grow Green's nitrogen concentration (4%) is double that of typical 2-1-6 liquids, you'll use less product to hit the same target EC. See our full guide to choosing the best hydroponic fertilizers for more detail on making the switch.
Yes — Grow Green provides only macronutrients (N, P, K, plus background Mg and S). You must pair it with Micro Green 2-0-3 to supply chelated trace elements including iron, manganese, zinc, copper, boron, and molybdenum. This separation allows precise micronutrient adjustment based on your water source and crop type.
Calcium and phosphorus form an insoluble precipitate (calcium phosphate) when mixed directly together. Adding Cal-Mag Plus to plain water first — before any phosphate-containing nutrients — prevents this reaction. Always follow the order: Cal-Mag → Micro Green → Grow Green → Blossom Green → pH adjustment last.
Grow Green contains double the nitrogen (4% vs. 2%) and slightly higher phosphorus compared to typical 2-1-6 liquid grow formulas. This means you use less product to achieve the same target ppm-N, compounding cost savings. The higher nitrogen also supports faster vegetative growth rates for heavy-feeding crops like tomatoes and cucumbers.
Yes. For soil, use the early vegetative rate (5 ml/gal stock solution) and apply when the top inch is dry. For coco coir, follow the hydroponic feeding schedule — coco requires daily watering and should never fully dry out. In both cases, check runoff EC periodically to prevent salt buildup in containers.
Stock solutions stored in a sealed, opaque container in a cool, dark place last 6+ months. The dry powder has an indefinite shelf life when kept dry and sealed. Always shake stock solutions before use as minor settling can occur. If you notice cloudiness or precipitation in the stock bottle, check that your mixing water doesn't contain hard water minerals — use RO or distilled water for stock preparation when possible.
Run a 1–2 week transition period rather than switching abruptly. During weeks 7–8, use 10 ml/gal of both Grow Green and Blossom Green simultaneously. Then drop Grow Green to 5 ml/gal in early bloom while increasing Blossom Green to 15 ml/gal. By peak bloom (week 11+), Grow Green drops to 0 and Blossom Green carries the program. This gradual shift prevents the nitrogen crash and yellowing that often occurs with abrupt formula changes. For a complete walkthrough, see our guide to growing hydroponic tomatoes.
If you're not completely satisfied, we offer a 90-day money-back guarantee. Return the unused portion in its original packaging and we'll process a full refund — no questions asked.
1% of all profits go to our foundation, focused on improving educational opportunities for children.
Check out our full FAQ page or contact our hydroponic experts for personalized advice on the 4-part system.
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