SKU: 20867520996
magnesium fertilizer for plants

magnesium fertilizer for plants 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

magnesium fertilizer for plants 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: 20867520996

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AngelKlein2275
Birmingham, US
★★★★★ 3
WEIRD feature - requires a water bottle
Color: Cow, Size: Large
Cute, but buyer beware. Maybe the description said this, but who would think to read for this.... You have to insert an empty bottle (like an old water bottle) for it to make the crinkle noise. There is a velcro spot at the base where you can open it and insert the water bottle for the noise factor and your dogs entertainment. I've yet to do that, but feel like my dog is gonna figure out the velcro and get the bottle out in no time. Seems like a waste of money. I could just give her an empty water bottle without the toy for free.
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Reviewed in the United States on June 9, 2026
A
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Alice
Battle Creek, US
★★★★★ 5
Best dog toy!
Color: Multicolor/Alligator & Wild Duck, Size: Medium, Color: Multicolor/Alligator & Wild Duck, Size: Medium
Best dog toy! Most dog toys lady maybe a week or less but this one has been going strong for almost 2 months. Both the squeekers still work on both toys i purchased. My vizsla loves ti squeek and carry it around. We added an empty water bottle in the pocket cavity for some extra fun! Yes, we are still on the same water bottle! Fantastic durability.
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Reviewed in the United States on May 26, 2026
A
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Amy Jo
Lake Worth, US
★★★★★ 3
Shows wear quickly
Color: Multicolor/Sheep & Cow, Size: Medium
These are cute but not holding up as well as I had hoped. Quality is ok and the Velcro has held up great. The fabric just isn’t as good as it could be. They are much larger than expected.
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Reviewed in the United States on April 28, 2026
R
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Rachel
Carnegie, US
★★★★★ 5
Super Sturdy with hours of fun.
Color: Wild Duck, Hare, Squirrel & Alligator, Size: Small
I got the small ones that you cannot put a water bottle in. These toys have held up way better than expected. I am dog sitting a very rough with toys dog named Chunk. He tears up ever. Single. Toy my dog (Ted) has. I bought new ones just for chunk. These appealed to me with the no stuffing, They were cheaper, and have a squeaker. Everything chunk needed. They arrived on time and I thought I wasted my money. They were super soft, like too soft. They felt flimsy and weak. Like 5 minutes with chunk and they be dead. 2 hours with my dog and they would have a rip. So far 2 of them (I set two out) have lasted the whole weekend. The bunny looks very rough and disgusting, but no rips, the squeakers still work, and no random fluff everywhere. I am going to wash the bunny once chunk leaves. My very careful doggo Ted loves them too. He throws them up in the air and catches them, plays tug of war with them, and no rips. They are super sturdy. He can’t wait until Chunk leaves (chunk is 2 and Ted is 12-13) so he can play with them.
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Reviewed in the United States on April 26, 2026
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Amber B.
Dallas, US
★★★★★ 5
Loved it
Color: Brown/Wild Duck, Size: Large, Color: Brown/Wild Duck, Size: Large
He loved it so much, he destroyed it so we ordered another. I didn't realize that you can stick an empty water bottle inside. Again, the first one didn't last long, but he enjoyed it
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Reviewed in the United States on May 20, 2026

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