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Magnesium Nitrate Fertilizer 11-0-0

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Weight: 2 Pounds

Magnesium Nitrate Fertilizer 11-0-0

Premium water-soluble Magnesium Nitrate delivers 11% nitrate nitrogen and 9.6% magnesium in one fast-acting formula — correcting deficiencies, fueling chlorophyll production, and supporting vigorous growth across soil, hydroponic, and foliar applications.

🧪 CDFA Registered 🇺🇸 Made in USA 🛡️ 90-Day Guarantee 🚚 Free Shipping $100+

Ideal Applications

Soil Drench
1–2 tsp/gallon
Hydroponics
50–100 ppm Mg
Foliar Spray
1 tsp/gallon
Fertigation
2–4 lbs/acre
FEATURES

🔬 11% Nitrate Nitrogen

Every nitrogen molecule is 100% nitrate (NO₃⁻) — immediately plant-available without microbial conversion, even in cold soils where ammonium uptake stalls.

🌿 9.6% Magnesium

Provides magnesium — the central atom of every chlorophyll molecule — at a concentration sufficient to correct deficiency and sustain peak photosynthetic output.

💧 100% Water Soluble

Dissolves completely with no residue, making it compatible with drip irrigation, NFT, DWC, ebb-and-flow, and foliar spray systems without clogging emitters.

⚖️ pH Neutral Formula

Unlike ammonium sulfate or Epsom salt, Magnesium Nitrate will not significantly acidify your growing medium, giving you stable pH with no corrective adjustments needed.

🅰️ Tank A Compatible

Safely mixes with Calcium Nitrate in concentrated Tank A stock solutions without precipitating — a critical advantage for two-part hydroponic programs.

❄️ Cold-Soil Performance

Nitrate nitrogen is taken up efficiently even when soil temperatures drop below 55°F, making this product reliable for cool-season crops and early spring applications.

🧪 Third-Party Tested

Every batch is independently tested for heavy metal content — results are consistently well below regulatory limits, with documentation available on request.

🏅 CDFA Registered

Registered with the California Department of Food and Agriculture, meeting strict labeling and content requirements for professional agricultural use.

🇺🇸 Made in USA Since 1989

Packaged at our Madera, California facility under quality controls developed over 35+ years of serving commercial growers and home gardeners.

🌾 Dual-Deficiency Correction

Corrects both magnesium and nitrogen deficiencies simultaneously — one product, one application, faster recovery than single-nutrient alternatives.

DERIVED FROM

Greenway Biotech's Magnesium Nitrate 11-0-0 is sourced from high-purity technical-grade materials and packaged at our California facility. The formula delivers two essential plant nutrients — magnesium and nitrate nitrogen — from a single ionic salt with no fillers or binders.

Primary Sources

Magnesium Nitrate

The primary ingredient — a highly soluble inorganic salt that delivers both nitrate nitrogen (11%) and magnesium (9.6%) in plant-available ionic form immediately upon dissolution.

Magnesium Oxide (MgO)

Expressed as 16% MgO on the guaranteed analysis label, consistent with standard fertilizer reporting conventions for magnesium content.

Guaranteed Analysis:

  • Total Nitrogen (N): 11% — as 11% Nitrate Nitrogen
  • Magnesium (Mg): 9.6%
  • Magnesium Oxide (MgO): 16%
SCIENCE BEHIND THE FORMULA

11-0-0: Nitrate Nitrogen + Magnesium — The Chlorophyll Pair

Plants need magnesium as the structural core of every chlorophyll molecule, and nitrate nitrogen to build the amino acids and proteins that drive growth. Magnesium Nitrate 11-0-0 delivers both nutrients together in a pH-neutral, immediately available ionic form — no soil microbial conversion required.

🌿 Nitrogen — 11% (Nitrate Form)

Nitrate nitrogen (NO₃⁻) is the most universally available nitrogen form across pH ranges and soil temperatures. Unlike ammonium, it doesn't require nitrification and doesn't contribute to acidification. In hydroponic systems, it keeps reservoir pH stable and prevents the swings associated with ammonium-based fertilizers.

💚 Magnesium — 9.6%

Magnesium is a mobile macronutrient that serves as the central atom of the chlorophyll porphyrin ring, activates over 300 enzymes, drives ATP synthesis and phosphate metabolism, and facilitates sugar transport from leaves to fruits and roots. Deficiency first appears as interveinal chlorosis on older, lower leaves — a pattern Magnesium Nitrate corrects at the source.

Why Magnesium Nitrate Outperforms Single-Nutrient Alternatives

🔬 Chlorophyll at the Molecular Level

Magnesium sits at the center of every chlorophyll molecule, bonded to four nitrogen atoms in a porphyrin ring. Without adequate Mg, the entire photosynthetic apparatus degrades — no amount of extra nitrogen will compensate for a chlorophyll structure that lacks its central atom.

⚡ Enzyme Activation

Magnesium activates RuBisCO (the primary carbon-fixing enzyme), ATP synthase, and RNA polymerase. These roles make adequate Mg essential not just for green color, but for carbohydrate production, energy transfer, and gene expression throughout the plant.

🔄 vs. Epsom Salt (MgSO₄)

Epsom salt provides magnesium plus sulfur but adds no nitrogen and slightly acidifies growing media. Magnesium Nitrate provides the same magnesium content (9.6% vs. Epsom's 9.8%) plus 11% nitrogen, at a neutral pH. Choose Mg Nitrate during vegetative and early flowering stages; switch to Epsom during late bloom when extra nitrogen isn't wanted.

🌡️ Cold-Weather Advantage

Nitrate nitrogen is taken up by active transport and is not dependent on soil microbial activity or temperature. When soils drop below 50°F and ammonium nitrification slows or stops, nitrate remains fully available — making Magnesium Nitrate the reliable choice for cool-climate crops and early-season applications.

Identifying Magnesium vs. Nitrogen Deficiency

Both are mobile nutrients — symptoms appear first on older, lower leaves. The key visual distinction:

  • Magnesium deficiency: Interveinal chlorosis — yellowing between the veins while the veins themselves stay green. Classic sign on older leaves, progresses upward if untreated.
  • Nitrogen deficiency: Uniform pale green or yellow across the entire leaf, including the veins. Older leaves fade first and may drop prematurely.
  • Both present: Magnesium Nitrate corrects both simultaneously — one application addresses the full deficiency picture.

Deficiency Correction Timeline

Day 1 Apply solution — nutrients enter root zone or leaf tissue
Days 3–7 Foliar applications show recovery — new growth emerges green
Weeks 1–2 Soil drench results visible — chlorosis halted in existing foliage
Weeks 2–3 Full recovery in new growth — healthy green color restored throughout canopy

Results vary with soil conditions, temperature, moisture, and severity of deficiency. Foliar applications consistently show faster visible response than soil drenches.

APPLICATION RATES & DIRECTIONS

Soil Drench & Garden Beds

Mix with water and apply directly to root zone
Crop / Use Rate Frequency Notes
General maintenance 1–2 tsp/gallon Every 2–4 weeks Apply to moist soil
Tomatoes 2 tsp/gallon Every 2 weeks Critical during flowering and fruit set
Leafy greens 1.5 tsp/gallon Every 2–3 weeks Throughout growing season
Citrus 3 tsp/gallon Spring & fall Apply under drip line
Cannabis 1–2 tsp/gallon Weeks 1–7 of flower Taper off in late flower

Foliar Spray

Spray directly on foliage for fast deficiency correction
Use Rate Frequency Notes
Deficiency prevention 1 tsp/gallon Every 7–14 days Apply before symptoms appear
Active deficiency correction 1.5 tsp/gallon Every 5–7 days until recovery Results visible in 3–7 days
Leafy greens (foliar) 0.5 tsp/gallon Every 7 days Light application only

Hydroponics & Fertigation

Maintain proper Mg levels in recirculating and run-to-waste systems
System Type Mg Target (ppm) Approx. Rate Notes
NFT / DWC 50–80 ppm 0.5–0.8 tsp/gal Add to Tank A; adjust for water source
Ebb & Flow 60–100 ppm 0.6–1 tsp/gal Higher for fruiting crops
Drip / Run-to-Waste 80–120 ppm 0.8–1.2 tsp/gal Account for runoff factor
Fertigation (field) 2–4 lbs/acre/week Calibrate injector before use

12-Week Tomato PPM Targets

Magnesium source and ppm targets across a 12-week fruiting cycle
Week Growth Stage Mg Source Mg (ppm) N from Mg Source (ppm)
1–2 Seedling Mg Nitrate 30–40 ~35
3 Early Veg Mg Nitrate 50 ~55
4–5 Late Veg Mg Nitrate 60–70 ~70
6–7 Early Bloom Mg Nitrate 70–80 ~80
8 Transition Mg Nitrate → Epsom Salt 60 ~30 (tapering)
9–10 Fruit Development Epsom Salt 50–60 0
11 Ripening Epsom Salt 40 0
12 Harvest None (flush) 0 0
HOW TO USE

Soil & Garden Beds

  1. Measure 1–2 teaspoons of Magnesium Nitrate per gallon of water.
  2. Add the fertilizer to the water (not water to powder) and stir until fully dissolved — the solution will be clear.
  3. Water soil lightly before applying to prevent root burn in dry conditions.
  4. Apply the solution evenly around the root zone, avoiding direct stem contact.
  5. Repeat every 2–4 weeks during the active growing season.

Foliar Spray

  1. Mix 1 teaspoon per gallon of water for prevention; 1.5 teaspoons per gallon for active deficiency correction.
  2. Apply early morning or late afternoon when temperatures are below 85°F.
  3. Spray the undersides of leaves as well as the tops — stomata are concentrated on leaf undersides.
  4. Allow solution to dry completely before exposing plants to direct sun.
  5. Repeat every 5–14 days depending on deficiency severity.

Hydroponics (A/B Two-Part System)

  1. Add Magnesium Nitrate to Tank A along with Calcium Nitrate and chelated iron.
  2. Keep Tank B separate — it holds phosphates (MKP, MAP) and sulfates (Epsom Salt). Never mix Mg Nitrate with phosphates in concentrated stock solutions.
  3. Target 50–100 ppm Mg in your working nutrient solution depending on crop and growth stage.
  4. Maintain nutrient solution pH between 5.5 and 6.5 for optimal uptake.
  5. Monitor EC alongside individual ppm targets — adjust as plants consume nutrients.

Fertigation (Drip Systems)

  1. Apply at 2–4 lbs per acre per week during active growth through calibrated injectors.
  2. Calibrate your injector ratio before the growing season — Mg Nitrate dissolves readily but verify concentration matches target ppm.
  3. Apply weekly during vegetative and early flowering stages; taper in late flower.

Pro Tip: Diagnosing Source Water Before You Formulate

Hard tap water often contains a Ca:Mg ratio of 6:1 or higher — far above the optimal 3:1 to 4:1 range. This calcium excess causes magnesium lockout even when adequate Mg is present in your nutrient solution. Before designing your program, run a basic water test. If your Ca:Mg ratio exceeds 5:1, use Magnesium Nitrate to bring it back into balance. RO water users should build their Ca:Mg ratio from scratch — target 3:1 to 4:1 with Calcium Nitrate and Magnesium Nitrate together.

When Magnesium Nitrate Is the Right Choice

  • During vegetative growth and early flowering when plants need both nitrogen and magnesium simultaneously.
  • In hydroponic Tank A programs where both Ca and Mg must be dosed without mixing issues.
  • When correcting interveinal chlorosis on older leaves while also driving new green growth.
  • In cool-weather conditions where nitrate nitrogen outperforms ammonium forms.
  • When pH stability matters and you can't afford the acidification from Epsom salt or ammonium sources.

When to Consider Other Options

  • During late flowering or ripening when additional nitrogen is not desired — switch to Epsom Salt for nitrogen-free magnesium plus sulfur to support terpene and essential oil production.
  • When you need magnesium only for wellness or bath use — Epsom Salt and Magnesium Chloride Flakes are better suited.
  • When correcting a sulfur deficiency simultaneously — Epsom salt delivers both Mg and S in a single product.
MAGNESIUM NITRATE CALCULATOR
SAFETY & HANDLING
Personal Protective Equipment (PPE)
  • Wear chemical-resistant gloves when handling powder or concentrated solutions.
  • Wear safety glasses or goggles — fine particles can cause eye irritation.
  • Use a dust mask or N95 respirator when measuring or pouring powder in enclosed spaces.
  • Wash hands thoroughly with soap and water after handling.
Storage Guidelines
  • Store in a cool, dry place in the original sealed container — Magnesium Nitrate is hygroscopic and will absorb moisture from the air if left open.
  • Keep away from direct sunlight and heat sources above 95°F.
  • Store away from oxidizable materials — Magnesium Nitrate is an oxidizer at high concentrations.
  • Keep out of reach of children and pets.
  • Do not store near food, feed, or beverage products.
Application Precautions
  • Always add fertilizer to water — never add water to dry powder in a small container.
  • Avoid applying foliar sprays in temperatures above 85°F or in direct midday sun to prevent leaf burn.
  • Do not mix concentrated Magnesium Nitrate with phosphate fertilizers (MAP, MKP) — use separate stock tanks.
  • Avoid contact with eyes, mucous membranes, and broken skin.
  • Do not apply to waterways, storm drains, or drainage ditches unless concentration complies with local regulations.
First Aid
  • Eye contact: Flush with clean water for at least 15 minutes, holding eyelids open. Seek medical attention if irritation or redness persists.
  • Skin contact: Remove contaminated clothing. Wash affected area with soap and water. Seek medical attention if irritation develops.
  • Ingestion: Do not induce vomiting. Rinse mouth with water. Contact Poison Control (1-800-222-1222) or seek medical attention immediately.
  • Inhalation: Move to fresh air immediately. Seek medical attention if coughing, shortness of breath, or other symptoms persist.

Refer to the Safety Data Sheet (SDS) for complete safety information.

COMPLETE YOUR SYSTEM
FREQUENTLY ASKED QUESTIONS
When should I use Magnesium Nitrate vs. Epsom Salt?

Use Magnesium Nitrate when your plants need both nitrogen and magnesium — during vegetative growth, early flowering, and any time foliar color is fading while nitrogen demand is still high. Use Epsom Salt during late flowering and ripening when extra nitrogen isn't desired, or when a sulfur boost supports terpene and oil production. Both products provide approximately the same magnesium content (~9.6–9.8%); the choice comes down to which companion nutrient — nitrogen or sulfur — your crop needs at that stage. For a deeper comparison, see our guide on Understanding Nutrient Deficiencies.

How quickly does it correct magnesium deficiency?

Foliar applications typically show visible improvement within 3–7 days — new growth emerges green and healthy. Soil drenches take 1–2 weeks for visible results as the magnesium moves into the root zone and is translocated upward. Note that existing chlorotic leaves may not fully recover their green color, but new growth will be normal. For fastest correction, combine a foliar spray (immediate) with a soil drench (sustained).

Can I mix Magnesium Nitrate with Calcium Nitrate?

Yes — Magnesium Nitrate and Calcium Nitrate are fully compatible in the same concentrated Tank A stock solution. Both are nitrate-based and will not precipitate together. However, keep Magnesium Nitrate separate from phosphate fertilizers (MKP, MAP) in concentrated stock solutions — mixing these together can form magnesium phosphate precipitates that clog lines and reduce nutrient availability. In dilute working solutions at normal application rates, all of these fertilizers can be combined without issue.

What is the ideal calcium-to-magnesium ratio?

The optimal Ca:Mg ratio for most crops is 3:1 to 4:1 in the nutrient solution or soil pore water. Ratios wider than 5:1 (too much calcium relative to magnesium) can induce magnesium lockout — the plant physically cannot take up Mg even when it's present, because calcium and magnesium compete for the same uptake channels. Hard tap water commonly has Ca:Mg ratios of 6:1 or higher, meaning you may need to add extra Magnesium Nitrate even if the absolute Mg level appears adequate. Learn more in our article on the function of magnesium in plants.

Is this safe to use in all hydroponic systems?

Yes — Magnesium Nitrate is 100% water soluble with no insoluble residue, making it safe for NFT, DWC, ebb-and-flow, and drip systems. It won't clog emitters or leave deposits in reservoirs. Add it to Tank A alongside Calcium Nitrate, target 50–100 ppm Mg in the working solution, and maintain pH between 5.5 and 6.5 for optimal uptake.

Does Magnesium Nitrate change soil or nutrient solution pH?

No — Magnesium Nitrate is pH neutral and won't significantly acidify your growing medium or reservoir. This contrasts with ammonium sulfate and some other nitrogen sources that lower pH over time. In hydroponic systems, Magnesium Nitrate is particularly valued because it allows you to dial in your pH without fighting acidification from the nitrogen source.

Why are the symptoms on older leaves instead of new growth?

Magnesium and nitrogen are both mobile nutrients — plants can redistribute (remobilize) them from older tissue to newer, actively growing tissue when supply runs short. This means deficiency symptoms appear first on the oldest, lowest leaves and progress upward as the plant continues to cannibalize older tissue to support new growth. By the time you see symptoms on young growth, the deficiency is typically severe. See our guide on nitrogen function in plants for more detail on nutrient mobility.

What is the A/B tank system and where does Magnesium Nitrate go?

A/B (or two-part) hydroponic systems use two concentrated stock tanks to prevent nutrient precipitation before dilution. Tank A holds calcium and nitrate fertilizers together: Calcium Nitrate, Magnesium Nitrate, Chelated Iron, and Potassium Nitrate. Tank B holds phosphates and sulfates: MKP (monopotassium phosphate), MAP, Epsom Salt (magnesium sulfate), and micronutrient blends. Magnesium Nitrate always goes in Tank A. Never combine Magnesium Nitrate with high-phosphate concentrates in the same stock tank — they will precipitate.

GROW WITH CONFIDENCE
Quality & Purity Standards

Every batch of Magnesium Nitrate 11-0-0 is sourced from high-purity technical-grade materials and independently tested for heavy metal content. Results are consistently well below the limits required by CDFA and standard fertilizer regulations. We maintain documentation for each production run and can provide test results upon request.

90-Day Guarantee

We stand behind the performance of our products. If you're not satisfied with your results within 90 days of purchase, contact us at questions@greenwaybiotech.com for a full refund — no questions asked.

California-Based Since 1989

Greenway Biotech, Inc. was founded in 1989 and is now based in Madera, California — in the heart of the San Joaquin Valley, one of the most productive agricultural regions in the world. Being close to our grower customers means our products are tested against the real-world demands of commercial agriculture, not just home gardens.

Sustainability & Packaging

We're actively evaluating compostable and reduced-plastic packaging options for our product line. Our Madera facility consolidates regional distribution, reducing shipping miles for customers throughout California's Central Valley and beyond.

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HAVE QUESTIONS?

Check out our full FAQ page or contact our experts for personalized advice on application rates, deficiency diagnosis, or building your nutrient program.

📧 questions@greenwaybiotech.com