Newmarket, Ontario (Head Office)
1175 Stellar Drive, Unit #5
Newmarket, ON L3Y 7B8
- Mon10:00am–6:00pm
- Tue10:00am–6:00pm
- Wed10:00am–6:00pm
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- Fri10:00am–6:00pm
- Sat10:00am–4:00pm
- SunClosed
$0.00 CAD
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GreenPlanet Nutrients Horti Grow is a fully soluble dry fertilizer for lush, green vegetative growth, built for growers who want consistent, scalable plant nutrition. This water-soluble powdered fertilizer is designed to support the vegetative stage of development with a clear, professional-grade profile.
Horti Grow is formulated to encourage lush, green growth and provide an optimal array of nutrients during vegetative development. It’s positioned as part of the horti line, where the focus stays on robust NPK ratios and specific micronutrients rather than extra add-ons. The formula is listed as 8-11-21, and it includes magnesium, sulfur, and micronutrients to round out vegetative-stage support in one soluble dry fertilizer.
Consistency is a core differentiator of the horti line, and Horti Grow is built with that same goal. These horti nutrients are described as science-based formulations backed by field testing, and they are tested before and after formulation to ensure high quality. The ingredients are described as chemically compatible and water-soluble, supporting reliable performance for growers who value repeatable batch-to-batch results.
The chemistry and cleanliness claims are also clear and practical for real-world horticulture systems. Horti nutrients are described as highly soluble and consistent in each batch, with pH stable performance. They contain no fillers or contaminants, and they contain zero sediment or organic material intended to block irrigation systems. If you want a soluble dry fertilizer that stays clean in solution and supports smooth operation in irrigation-driven setups, Horti Grow is built around that expectation.
Beyond the basics, the horti line is positioned around efficiency and crop performance, with superior plant uptake rates described to support crop productivity and higher yields. Horti Grow keeps that promise focused on the vegetative stage: steady vegetative nutrition, a robust NPK ratio, and micronutrient support in a fully soluble, professional format. This is a good fit for growers running production-style gardens who want a consistent vegetative stage fertilizer designed for stock tanks, injection systems, and irrigation-focused horticulture without unnecessary complexity.
Step-by-step mixing and feeding instructions for Green Planet Nutrients Horti Grow - 5 LBS.
Fill your reservoir or watering container with clean, room-temperature water first. Shake the bottle of Green Planet Nutrients Horti Grow - 5 LBS well before every use. Using the feeding schedule below, measure the recommended dose and add it directly to the water while stirring. Allow the solution to mix fully before adding any other fertilizers, additives, or supplements.
Always add nutrients to water — not the other way around. Mix thoroughly between products to ensure an even, stable nutrient solution.
Vegetative stage — Horti Grow
Flowering stage — Horti Grow
Warning – Important Safety Information
This product may cause mild skin irritation and eye irritation. Avoid unnecessary contact with skin, eyes, and clothing. Use only as directed.
General safety precautions
Read and follow all instructions on the product label and any accompanying documentation before use. Keep out of reach of children and pets. Do not ingest. Avoid breathing vapours, mist, or dust that may be generated during handling or use.
Wear appropriate personal protective equipment (PPE), such as protective gloves, long sleeves, long pants and closed-toe footwear. When there is a risk of splashing or airborne particles, use safety glasses or other suitable eye and face protection.
First aid – skin contact
IF ON SKIN OR HAIR: Remove contaminated clothing immediately. Rinse skin with clean water for several minutes, then wash with mild soap and water. If irritation or redness develops and persists, seek medical attention. Wash contaminated clothing before reuse.
First aid – eye contact
IF IN EYES: Rinse cautiously with clean water for several minutes, keeping eyelids open. Remove contact lenses if present and easy to do. Continue rinsing. If irritation persists, obtain medical advice.
First aid – ingestion and inhalation
IF SWALLOWED: Rinse mouth thoroughly with water. Do not induce vomiting unless instructed by a medical professional. Seek medical attention if you feel unwell.
IF INHALED: Move the person to fresh air and keep them comfortable for breathing. If coughing, breathing difficulty, dizziness or other symptoms occur, seek medical assistance.
Storage and handling
Store this product in its original closed container, in a cool, dry and well-ventilated area. Protect from extreme temperatures and direct sunlight. Keep container tightly sealed when not in use.
Avoid release to drains, natural waterways or outdoor soil. Dispose of unused product and empty containers in accordance with local regulations and the directions on the label.
Important: If medical advice is needed, keep the product label or container available. Always follow the specific instructions and safety recommendations provided by the manufacturer. This safety notice is intended as general guidance and does not replace official label directions or documentation.
| Total Nitrogen (N) | 8.0% |
|---|---|
| Ammoniacal Nitrogen (N) | 3.0% |
| Nitrate Nitrogen (N) | 5.0% |
| Available Phosphate (P2O5) | 11.0% |
| Soluble Potash (K2O) | 21.0% |
| Water Soluble Magnesium (Mg) | 2.5% |
| Sulfur (S) | 5.5% |
| Boron (B) | 0.06% |
| Chelated Copper (Cu) | 0.02% |
| Chelated Iron (Fe) | 0.3% |
| Chelated Manganese (Mn) | 0.09% |
| Molybdenum (Mo) | 0.009% |
| Total Zinc (Zn) | 0.02% |
Ammoniacal Nitrogen (N) is a plant-available form of ammonium (NH₄⁺) that provides a steady, gentle source of nitrogen for healthy green growth. Unlike fast-release nitrogen types, ammoniacal nitrogen feeds plants slowly, helps stabilize root-zone pH, and works well in cooler temperatures. It is commonly used during early vegetative growth because it supports strong leaf development without burning young roots. If plants show pale leaves, slow growth, or weak stems, they may need more available ammoniacal nitrogen.
Ammonium sulfate is unique because it delivers fast ammonium nitrogen plus plant-ready sulfate sulfur in one ingredient, and it can gently acidify the root zone over time, which matters for nutrient availability. This makes it especially useful when plants are pale and slow from true nitrogen and sulfur shortage, but it also means overuse can cause salt stress or pH drift faster than many other options.
Available Phosphate (P₂O₅) supports root development, energy transfer, and early structural growth by providing a form of phosphorus that plants can absorb and use quickly.
Boron is essential because it stabilizes cell walls, supports root and shoot growth, and regulates sugar movement throughout the plant. What makes boron unique is its limited mobility and extremely narrow range between deficiency and excess, which causes new growth to show symptoms rapidly when levels fall out of balance.
Chelated copper is important because it supports key enzyme systems that drive energy flow, strong tissue formation, and healthy new growth, while chelation keeps copper available and stable in the root zone. It’s unique because plants need it in extremely small amounts and it can become unavailable or toxic more easily than many other micronutrients, so chelated forms help deliver precise, predictable copper without big swings.
Chelated iron is important because it keeps iron usable for plants even when growing conditions would normally lock iron out, helping prevent the classic yellow-new-leaf symptom caused by low chlorophyll production. It is unique from other iron sources because the chelation protects iron from becoming insoluble, making it a more reliable way to correct iron-related chlorosis when regular iron can fail.
Chelated manganese is important because it keeps manganese available for photosynthesis and enzyme activity even when pH or water chemistry would normally lock it out, and it’s unique from similar micronutrients because it strongly supports the plant’s energy-processing systems that drive healthy, resilient new growth.
Copper EDTA helps keep copper dissolved and available to roots longer, so plants can absorb it more consistently when copper would otherwise tie up in the growing medium. It’s important because copper supports enzyme activity and healthy new growth, and it’s unique because the chelate improves predictability while allowing very small, controlled copper dosing.
Molybdenum is important because it helps plants convert nitrogen into usable building blocks for chlorophyll and growth, and it’s unique from many nutrients because it mainly supports enzyme-driven “nutrient use” rather than directly building plant tissue.
Nitrate Nitrogen provides a stable, easy-to-absorb form of nitrogen that supports steady growth, strong foliage, and reliable plant development without sudden nutrient swings.
Soluble potash (K2O) is important because it helps plants control water use, move sugars to new growth and fruit, and build stronger, higher-quality structure under stress. It’s unique from many other nutrients because it acts more like a regulator and transport helper than a direct “building material,” so the biggest benefits show up as steadier growth, stronger stems, and better finishing instead of just bigger leaves.
Sulfur is important because plants need it to build key amino acids and proteins that drive real growth, strong structure, and efficient use of nitrogen, making it uniquely different from “look-alike” nutrients that may change leaf color without supporting the plant’s core building process.
Total Nitrogen is important because it directly drives leafy growth, chlorophyll production, and overall growth speed, which sets the pace for the entire plant. It’s unique because the “total” number can include different nitrogen forms that behave differently in the root zone, meaning the same total amount can produce very different results depending on the nitrogen type and plant stage.
Total Zinc (Zn) matters because zinc controls key growth processes that affect leaf size, healthy new shoots, and normal development, and low zinc often causes stunting even when everything else seems correct. It’s unique from many other nutrients because plants need it in tiny amounts and it’s often present but “locked up” by pH or nutrient imbalance, so the challenge is availability—not just quantity.
Water soluble magnesium is important because it quickly restores the plant’s ability to make chlorophyll and produce energy, which helps stop interveinal yellowing on older leaves and improves overall nutrient use; it’s unique because it becomes available immediately in water, making it faster and more predictable than slower magnesium sources.
Iron EDTA keeps iron dissolved and available long enough for roots to absorb it, which is why it can quickly improve new growth color when iron is tied up in the root zone. It’s unique because the EDTA chelate balances stability and accessibility, making iron more reliably usable in mildly acidic to near-neutral conditions compared to many non-chelated iron forms.
Manganese EDTA is unique because the EDTA chelate keeps manganese stable and more available during delivery, helping plants absorb it more reliably when manganese would otherwise lock up. This matters because manganese drives key enzyme functions tied to photosynthesis and healthy new growth, so consistent availability can prevent pale, chlorotic young leaves and stalled vigor.
Monoammonium phosphate feeds roots with phosphate for energy transfer and ammonium nitrogen for fast tissue building, which is why it can boost early rooting and growth more quickly than many other phosphorus sources. It’s unique because the ammonium portion can change root-zone pH and nutrient availability, so using it correctly supports roots, but overusing it can trigger imbalances that look like other deficiencies.
Potassium nitrate is often better for quick correction when the plant needs both potassium and fast nitrate nitrogen, because it dissolves cleanly and is taken up quickly, unlike potassium sources that don’t supply nitrogen. It’s unique because it can restore leaf color and growth momentum while also improving water regulation, but it can backfire if nitrogen is already high or if salt levels are already stressing the roots.
Zinc EDTA is important because it keeps zinc available in the root zone when pH or water chemistry would normally tie zinc up, helping new growth develop normally before deficiency symptoms get worse. It’s unique from other zinc forms because the EDTA chelate shields zinc in solution, making delivery more consistent when conditions are not ideal.

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