SKU: 78922371987
micronutrient-rich plant fertilizer

micronutrient-rich plant fertilizer GS Plant Foods Cal-Mag Extreme Liquid 1 Gallon Fertilizer with Calcium, Magnesium, Iron And Sulfur Supplement, Corrects Secondary Nutrient & Trace

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Description

micronutrient-rich plant fertilizer GS Plant Foods Cal-Mag Extreme Liquid 1 Gallon Fertilizer with Calcium, Magnesium, Iron And Sulfur Supplement, Corrects Secondary Nutrient & TraceCal Mag Extreme GS Plant Foods Cal Mag Extreme Advanced Calcium, Magnesium & Micronutrient Supplement for Plants Strengthens Cell Walls, Prevents Deficiencies & Promotes Vigorous Growth For All Plants, Lawns & Gardens Correct Deficiencies. Strengthen Growth. Supercharge Results. GS Plant Foods Cal Mag Extreme delivers the critical secondary and micronutrients plants need for healthy, balanced growth. Formulated with highly available sources of Calcium

Cal-Mag Extreme

GS Plant Foods Cal-Mag Extreme – Advanced Calcium, Magnesium & Micronutrient Supplement for Plants – Strengthens Cell Walls, Prevents Deficiencies & Promotes Vigorous Growth – For All Plants, Lawns & Gardens

Correct Deficiencies. Strengthen Growth. Supercharge Results.

GS Plant Foods Cal-Mag Extreme delivers the critical secondary and micronutrients plants need for healthy, balanced growth. Formulated with highly available sources of Calcium and Magnesium, it also includes Sulfur, Iron, Manganese, Zinc, Boron, and Molybdenum to ensure complete nutritional support.

Calcium and magnesium are often overlooked—but they are essential for building strong cell walls, maintaining chlorophyll production, and supporting the transport of nutrients throughout the plant. Deficiencies in these elements can lead to weak stems, yellow leaves, blossom end rot, and reduced yield.

Cal-Mag Extreme prevents these problems before they start—keeping your plants strong, green, and highly productive.

 

💪 COMPLETE NUTRIENT SUPPORT: Cal-Mag Extreme provides essential Calcium (2.5%) and Magnesium (1.0%)—plus Sulfur, Iron, Manganese, Zinc, Boron, and Molybdenum—to correct deficiencies and maximize nutrient balance in your plants.

🌿 BUILDS STRONGER PLANTS: Calcium fortifies cell walls and prevents common issues like blossom end rot, while magnesium supports chlorophyll production for lush, dark-green foliage.

OPTIMIZES NUTRIENT UPTAKE: Enhances the absorption and mobility of nitrogen, phosphorus, and potassium—making your fertilizer more effective and reducing nutrient lockout.

🌸 BOOSTS GROWTH & FLOWERING: Strengthens roots, improves nutrient flow, and promotes more consistent flowering and fruiting across all plant types.

🌎 SAFE & EASY TO USE: 100% soluble and compatible with all fertilizers, hydroponic systems, and soil types. Non-toxic, environmentally safe, and suitable for all plants, indoors and outdoors.

What is Cal Mag 420 Dry?

GS Plant Foods Cal Mag 420 Dry Super Concentrate is our Dry, powdered version. Your all-in-one solution for robust plant health and unstoppable growth! This water-soluble powder delivers a powerhouse blend of calcium (13%), magnesium (3%), and sulfur (4%)—critical secondary nutrients that fortify cell walls, boost photosynthesis, and shield plants from disease. As an effective cal mag plant food for plants, it provides essential support for healthy development. With just ¼ teaspoon per gallon, one 18-ounce jar makes 420 gallons of nutrient-rich solution, perfect for soil, hydroponics, coco coir, and container gardens. 🌿

Key Benefits

💪 Stronger Plants: Natural cal mag for plants helps strengthen cell walls with calcium and boosts chlorophyll production with magnesium for lush, vibrant growth.

🛡️ Disease Defense: Cal mag fertilizer enhances natural resistance to pests, mold, and environmental stressors.

🌞 Optimized Photosynthesis: Sulfur ensures efficient nutrient mobility and energy conversion.

🌍 Universal Compatibility: Safe for all growth stages—seedling to bloom—and all growing mediums.

💧 Zero Waste: 100% water-soluble cal-mag for plants formula leaves no residue, ensuring full nutrient absorption.

Ingredient Breakdown

  • Calcium (13%): Builds robust cell structure and improves root-to-shoot nutrient flow when you add Cal-Mag for plants.

  • Magnesium (3%): Core component of chlorophyll for deeper greens and higher yields.

  • Sulfur (4%): Cal-Mag fertilizer supports enzyme production and amino acid synthesis.

  • Guaranteed Analysis: 11% nitrate nitrogen, pH-balanced for seamless integration with any regimen.

  • Derived From: Calcium nitrate and magnesium sulfate—pure, plant-ready nutrients.

What is Cal Mag 420 Dry?

GS Plant Foods Cal Mag 420 Dry Super Concentrate is our Dry, powdered version. Your all-in-one solution for robust plant health and unstoppable growth! This water-soluble powder delivers a powerhouse blend of calcium (13%), magnesium (3%), and sulfur (4%)—critical secondary nutrients that fortify cell walls, boost photosynthesis, and shield plants from disease. As an effective cal mag plant food for plants, it provides essential support for healthy development. With just ¼ teaspoon per gallon, one 18-ounce jar makes 420 gallons of nutrient-rich solution, perfect for soil, hydroponics, coco coir, and container gardens. 🌿

How to Use Cal-Mag Extreme

Simple Mix & Grow:

  1. Dilute: Stir ¼ teaspoon into 1 gallon of water (1 jar = 420 gallons!).

  2. Apply Weekly: Use as a root drench during irrigation for soil, coco, or hydroponic systems.

  3. Avoid Foliar Spray: Cal-mag fertilizer designed specifically for soil and root absorption only.

Pro Tip: Cal-Mag Extreme Liquid or Cal-Mag Dry 402 for plants pairs perfectly with primary nutrients for a complete feeding program!

Frequently Asked Questions:

Q: What is Cal-Mag Extreme?
A: balanced blend of Calcium, Magnesium, and essential micronutrients that strengthens plants, prevents deficiencies, and improves nutrient uptake. Safe and effective for all plants and growing systems.

_____________________________________________________________________________

Q: What makes Cal-Mag Extreme different from other Cal-Mag products?
A: Cal-Mag Extreme contains a complete suite of micronutrients (Fe, Mn, Zn, B, Mo) in addition to calcium and magnesium—ensuring balanced nutrition, faster uptake, and superior growth compared to basic two-element blends.


Q: How do I know if my plants need Cal-Mag?
A: If you see yellowing leaves, weak stems, blossom end rot, or poor fruit development, your plants are likely deficient in calcium or magnesium. Cal-Mag Extreme restores proper nutrient balance fast.


Q: Can I mix this with my fertilizer or kelp?
A: Absolutely. Cal-Mag Extreme is 100% compatible with all GS Plant Foods fertilizers, including Liquid Fish, Liquid Kelp, and Root Ruckus. It helps your plants make better use of those nutrients.


Q: Is this safe for edible crops and hydroponics?
A: Yes—Cal-Mag Extreme is completely soluble and safe for all growing environments, including hydroponic and aquaponic systems, greenhouses, and food crops.


Q: How often should I apply it?
A: Apply every 1–2 weeks during active growth, or whenever deficiencies are suspected. Regular use promotes steady, balanced nutrition and prevents future issues.

 

 

Applying a calcium-magnesium product can benefit various types of plants, especially those that require sufficient levels of these essential minerals for their growth and development. Calcium and magnesium are both important secondary nutrients for plants, playing vital roles in various physiological processes. Plants that can benefit from the application of a calcium-magnesium product include:

 

Tomatoes: Tomatoes require an adequate supply of calcium to prevent disorders like blossom end rot, which can affect fruit quality.

 

Peppers: Peppers benefit from balanced calcium and magnesium levels for proper fruit development and resistance to stress.

 

Cucumbers: Cucumbers also need sufficient calcium and magnesium to support healthy fruiting and prevent issues such as bitter-tasting cucumbers.

 

Leafy Greens: Plants like lettuce, spinach, kale, and other leafy greens benefit from calcium and magnesium for leaf development and overall plant vigor.

 

Broccoli and Cauliflower: These brassica vegetables can benefit from calcium and magnesium for healthy head formation and reduced susceptibility to diseases.

 

Beans: Both bush and pole beans benefit from adequate calcium and magnesium for proper pod development and overall plant growth.

 

Apples: Apple trees require calcium and magnesium for strong cell walls, which can improve fruit quality and storage ability.

 

Grapes: Grapes benefit from balanced calcium and magnesium levels for improved berry development and disease resistance.

 

Citrus Trees: Citrus trees need calcium and magnesium for healthy fruit formation and reduced susceptibility to nutrient deficiencies.

 

Potatoes: Potatoes can benefit from calcium and magnesium to prevent common issues like hollow heart and improve tuber quality.


Shipping Notes
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SKU: 78922371987

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Kelly
Port Orchard, US
★★★★★ 5
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Size: Medium/Large, Color: Illana the Iguana - Large
Mr. Iguana is a house favorite! I got my first one of these in a barkbox and my dog loved it so much, i went on the hunt for another one. Amazon saved the day! I own about 7 of these now. They are prefect for dogs just love to chew, they hold up great! And they are heavy duty, super easy to clean! My dogs are very happy, great value for the money! Doesn't have a smell, vibrant colors! Noise level is quiet, minus my dogs chewing !
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on August 13, 2025
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Verified Purchase
sec682
Chelsea, US
★★★★★ 3
Not for strong chewers
Size: Medium/Large, Color: Dog Ness Monster - Large
Initially, I really liked this for my dog. She is about 8 months old and still loves to chew and destroys most toys in a few minutes. When we got this, it seemed like it would hold up for a while despite being clearly gnawed on. Unfortunately, once she focused on the softer "water" portion of the toy, that is where things went downhill with this toy. After a few short chew sessions, she was tearing chunks out of it. We had purchased a replacement since she liked the original so much, and after about 5 minutes with the replacement, she had taken enough out of the blue section that we immediately threw that one out as well. Overall while the green portion held up, the blue didn't. I can't recommend this for strong chewers.
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Reviewed in the United States on December 8, 2025
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Verified Purchase
Gary Hugo
Whiting, US
★★★★★ 4
Definitely not indestructable
Size: Medium/Large, Color: Dog Ness Monster - Large, Size: Medium/Large, Color: Dog Ness Monster - Large
I have a 1-year-old toy fox terrier (Rocky, pictured). He has been chewing on this toy for seven months now; it is one of his favorites. He has been unable to seriously damage the "ocean" portion of this toy, but as you can see from the provided image, the sea serpent has not faired that well. It is missing its snout and smaller portions of the humps. My guess is that the advertiser images showing much larger dogs with "like new" versions of the toy are just that...NEW AND UNCHEWED. I have not had to clean up bits of this toy from my floor, so I assume Rocky has been swallowing them. My hope is that the yellow material of the serpent is not chemically dangerous when exposed to digestive fluids. Rocky easily destroys plush toys in a matter of days if not hours and, consumed pieces of a small microfiber blanket that he liked to toss around and play tug-of-war with (past tense as he destroyed it and has since been trashed after I began finding feces-stained undigested pieces of it lying around). Since this toy has survived seven months and has remained recognizable, I have to agree it is durable. Just beware, if my small toy fox terrier can damage the toy as pictured, expect your large breed chewer to do similar or worse damage. Also, the toy is very heavy! When Rocky drops it down a flight of stairs, it makes a MAJOR thud at the bottom, and sometimes makes me wonder if it might crack the large tile at the bottom. I cautiously recommend the product. Note the yellow frisbee in Rocky's picture. It is only a few months old and surprisingly has not suffered any chew damage despite substantial abuse. It appears to bend in the wind like a proverbial reed, evading damage by yielding to pressure.
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Reviewed in the United States on July 5, 2024
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Verified Purchase
Elaina rice
Bozeman, US
★★★★★ 5
Dog loves it! For tough chewers for sure
Size: Medium/Large, Color: Dog Ness Monster - Large, Size: Medium/Large, Color: Dog Ness Monster - Large
Dog absolutely loves it, he’s super rough on all of his toys they usually last about 10 minutes bore they are torn to shreds. It’s lasting through his chewing so I’m happy. It’s also super cute.
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Reviewed in the United States on April 9, 2026
M
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miriana
Houston, US
★★★★★ 5
Loch Yes
Size: Medium/Large, Color: Dog Ness Monster - Large, Size: Medium/Large, Color: Dog Ness Monster - Large
Cute toy, dog really likes it. I had my doubts when I pulled it out, and honestly so did she, but the soft part bounces, so that got her going. We've had it for about a week. My dog is ~70 lbs and a moderate chewer, and this monster still gets regular play and is holding up well.
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Reviewed in the United States on April 18, 2026

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