Calcium Nitrate Fertilizer 15.5-0-0 (Ammonia Calcium Nitrate 15.5-0-0)
- Regular Price
- $ 24.99
- Sale Price
- $ 24.99
- Regular Price
- $ 19.99
- Unit Price
- per
Calcium Nitrate Fertilizer 15.5-0-0
Premium ammonium calcium nitrate with 15.5% nitrogen and 19% calcium. Fast-acting, 100% water-soluble formula prevents blossom end rot, strengthens cell walls, and delivers dual nutrients efficiently. Perfect for tomatoes, peppers, and all calcium-hungry crops in soil or hydroponic systems.
Prevent Blossom End Rot Timeline
(Begin monitoring)
(Apply now!)
(Continue biweekly)
(No BER damage)
⚡ Quick Dose Guide
Select an application type for instant dosing recommendations.
≈2 cups per pound | Use the calculator below for precise measurements
⚠️ Critical Compatibility Alert
- NEVER mix directly with phosphate fertilizers (MAP, DAP, or any phosphorus solutions) - causes immediate precipitation
- In hydroponics: Add calcium nitrate and phosphate sources separately to your reservoir
- Apply when fruits are walnut-sized for best blossom end rot prevention
- Water thoroughly after soil application
- For foliar spray, apply early morning or evening to avoid leaf burn
- Store in cool, dry place away from moisture
🛡️ 19% Calcium
Essential for cell wall strength, prevents blossom end rot and tip burn in vegetables.
⚡ 15.5% Nitrogen
Fast-acting nitrate and ammonium nitrogen for immediate and sustained growth.
💧 100% Soluble
Completely dissolves for soil, hydroponic, and foliar applications.
PERFECT FOR THESE APPLICATIONS
COMMON PROBLEMS? WE HAVE SOLUTIONS
WHY GROWERS CHOOSE THIS FORMULA
🎯 Dual-Action Formula
Delivers both fast-acting nitrogen AND calcium in one application - no need for multiple products.
⚖️ pH Neutral
Won't raise pH like lime or acidify like ammonium sulfate. Perfect for maintaining optimized soil conditions.
🌿 Phosphorus-Free
Ideal for areas with phosphorus runoff concerns. No environmental P loading.
⚡ Immediate Availability
100% water-soluble for instant uptake. Works faster than gypsum or lime for rapid deficiency correction.
BLOSSOM END ROT PREVENTION GUIDE
Understanding Blossom End Rot
Blossom end rot (BER) appears as dark, sunken, leathery spots on the bottom of fruits. It's caused by calcium deficiency in developing fruit tissue - even when soil calcium is adequate. Inconsistent watering and rapid growth increase BER risk by disrupting calcium transport.
40-60% crop loss potential
Maximum marketable yield
Prevention Strategy: Apply calcium nitrate when fruits are walnut-sized and continue every 2 weeks. Maintain consistent watering and mulch to reduce stress. Foliar applications provide rapid correction during high-risk periods.
NPK FORMULA EXPLAINED
15.5-0-0 + 19% Calcium: The Dual-Nutrient Formula
This formula combines fast-acting nitrogen with essential calcium in a single, highly soluble product. The nitrogen comes in both nitrate (immediately available) and ammonium (sustained release) forms for balanced uptake.
N - 15.5%
Nitrogen
Drives vegetative growth, chlorophyll production, and protein synthesis. Dual nitrate/ammonium forms provide both immediate and sustained nutrition.
Ca - 19%
Calcium
Strengthens cell walls, prevents blossom end rot, and improves fruit firmness. Essential for cell division and nutrient transport.
Solubility
100% Water Soluble
Dissolves completely for uniform distribution through drip, spray, or hydroponic systems. No residue or clogging.
APPLICATION RATES & INSTRUCTIONS
Mix into topsoil or dissolve in water. Always water thoroughly after application.
📅 Seasonal Application Guide
🍅 Tomatoes & Peppers
| Stage | Rate | Frequency |
|---|---|---|
| At Planting | 1-2 lb/100 sq ft | Once |
| First Fruit Set | 2-3 lb/100 sq ft | Once |
| Maintenance | 1 lb/100 sq ft | Every 2-3 weeks |
🥬 Leafy Vegetables
| Type | Per Plant | Per 100 sq ft |
|---|---|---|
| Lettuce | 1 tbsp | 2-3 lb |
| Cabbage | 2 tbsp | 3-4 lb |
| Spinach | 1 tsp | 2 lb |
💧 Hydroponic Systems
| System | Rate | EC Contribution |
|---|---|---|
| NFT/DWC | 1-2 tsp/gal | 0.5-1.0 mS/cm |
| Ebb & Flow | 1.5 tsp/gal | 0.75 mS/cm |
| Drip/DTW | 1 tsp/gal | 0.5 mS/cm |
🍃 Foliar Application
| Crop | Rate | Coverage |
|---|---|---|
| Tomatoes | 1-2 tbsp/gal | 100-200 sq ft |
| Fruit Trees | 2 tbsp/gal | 5-10 trees |
| Vegetables | 1 tbsp/gal | 200 sq ft |
CALCIUM NITRATE CALCULATOR
COMPARE WITH OTHER CALCIUM SOURCES
| Feature | Calcium Nitrate | Gypsum | Lime |
|---|---|---|---|
| Calcium % | 19% | 23% | 32% |
| Nitrogen % | 15.5% | 0% | 0% |
| Water Solubility | 100% | Low | Very Low |
| Speed of Action | Immediate | Slow | Very Slow |
| pH Effect | Neutral | Neutral | Raises pH |
| Best For | Quick correction + growth | Clay soils | Acidic soils |
COMPLETE YOUR SYSTEM
Complete your nutrition program with these complementary products
Potassium Sulfate 0-0-50
Add potassium for fruit quality and disease resistance. Calcium nitrate provides N+Ca, this completes the K.
EssentialMKP 0-52-34
Phosphorus and potassium boost for flowering and fruiting. Apply separately from calcium nitrate!
OptionalEpsom Salt (Magnesium Sulfate)
Complements calcium with magnesium for complete secondary nutrient coverage.
OptionalChelated Iron DTPA
Prevent iron chlorosis alongside calcium nutrition. Essential for hydroponic systems.
QUICK REFERENCE GUIDE
📋 Application Quick Reference
3-4 lb/100 sq ft
At walnut-sized fruit
1-2 tbsp/sq ft
Every 4-6 weeks
1-2 tsp/gallon
EC 0.5-1.0 mS/cm
1-2 tbsp/gallon
Weekly during stress
≈2 cups per pound | Never mix directly with phosphate fertilizers
GROW WITH CONFIDENCE
Product Quality Guaranteed
- CDFA Registered - California Department of Food & Agriculture
- Commercial Grade - Same quality used by professional growers
- Made in USA - Manufactured in California since 1989
- Heavy Metal Tested - Third-party verified purity
- 100% Water Soluble - Solution grade for all application methods
Hassle-Free Return Policy
We stand behind our products with a 90-day satisfaction guarantee. If you're not completely satisfied with your purchase, contact our team for a full refund - no questions asked.
Expert Support Included
Our agricultural specialists are available Monday-Friday, 7AM-5PM PST to answer your questions about application rates, compatibility, and growing strategies. Call us or email anytime!
FREQUENTLY ASKED QUESTIONS
Q What is calcium nitrate?
Calcium nitrate provides nitrogen (15.5%) as nitrate and ammonium forms, plus calcium (19%) as Ca²⁺. It dissolves completely for immediate availability. Essential for preventing blossom end rot and strengthening cell walls.
Q Does it prevent blossom end rot?
Yes! The 19% calcium content effectively prevents blossom end rot in tomatoes, peppers, and squash. Apply when fruits are walnut-sized for best results. Continue applications every 2 weeks during fruit development.
Q When should I apply it?
Apply at planting, then again when fruits are walnut-sized. This is the critical period when calcium demand is highest. Also apply after heavy rain or during drought stress when calcium uptake is impaired.
Q Can I use it in hydroponics?
Yes! Use 1-2 tsp per gallon for EC contribution of 0.5-1.0 mS/cm. Never mix directly with phosphate solutions - add separately. Ideal for NFT, DWC, and ebb & flow systems.
Q How does it compare to gypsum?
Unlike gypsum, calcium nitrate provides immediately available calcium AND nitrogen. It works faster and is ideal for rapid correction. Gypsum is better for clay soils, while calcium nitrate excels in all growing media.
Q Will it prevent blossom end rot in cucumbers and squash?
Yes! Calcium nitrate is highly effective for all cucurbits including cucumbers, zucchini, squash, and melons. Apply 2-3 lb per 100 sq ft at planting and when fruits begin forming. The fast-acting calcium prevents the characteristic brown, sunken spots.
Q Does it help with tip burn in lettuce and cabbage?
Absolutely. Tip burn in leafy greens and brassicas is often caused by calcium deficiency. Apply 1.5-2 lb per 100 sq ft for lettuce, or 3-4 lb per 100 sq ft for cabbage and broccoli. The nitrate nitrogen also promotes vigorous leaf growth.
Q Can it prevent bitter pit in apples?
Yes, calcium nitrate is commonly used in orchards to prevent bitter pit in apples and pears. Apply as a foliar spray at 2 tbsp per gallon, starting at petal fall and continuing every 2-3 weeks through fruit development.
Q What about mixing with other fertilizers?
Never mix directly with phosphate solutions - add separately to avoid precipitation. Compatible with most other nutrients when dissolved in water. In hydroponics, always add calcium nitrate to the reservoir first, then add phosphates from the opposite end.
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