SKU: 8635502618

Cal-Mag Extreme – Advanced Calcium & Magnesium for Plants

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Description

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

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

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
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 8635502618

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4.8 ★★★★★
Based on 24 reviews
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A
Verified Purchase
Amazon Customer
Port Orchard, US
★★★★★ 3
Great, but didn’t last
Style: Black chew toys for dogs, Style: Black chew toys for dogs
I have a 70 pound pitbull and he absolutely loves this toy. Unfortunately, within a couple of hours this toy started to crumble. Now, there are large crumbs breaking off that he started eating, so we have to toss it. He’s only had this for two weeks.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on January 8, 2026
J
Verified Purchase
Julie Ann laclair
Massapequa, US
★★★★★ 5
Great value for a great price
Style: Black chew toys for dogs
My dogs loves it!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 27, 2026
B
Verified Purchase
Betsy
Grantham, US
★★★★★ 5
One of the best dog toys I’ve found
Color: Blue, Color: Blue
My Great Dane puppy- at 140lbs, loves this!! We had another one that was plastic and it worked ok but this is so much better! Interactive, soft to play with, battery last a long time & he does not get bored with it. Besides is plush lamb chops, best toy ever bought for him.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 25, 2026
K
Verified Purchase
K. Brittain
Los Angeles, US
★★★★★ 5
Keeps my wild child busy!
Color: Orange
*UPDATE 1/10/26* Does my pup love it? Yes. 5 stars for that. His big thing is just holding it in his mouth though, and laying down with it. Then he will put it down, and as soon as it rolls away he gets up and grabs it again. He definitely requires attention from his humans when it’s turned on…kind of defeats the purpose of why I bought it! He’s a needy boy, that’s for sure, so it’s not the toy’s fault. Two improvements I’d love to see though, are 1) the ability to turn off that yappy bark. I think my dog is more excited about it moving and not so much the yapping. Not that it’s bad, but my boy doesn’t bark much so I’m used to a quieter household. And 2) when removing the base for powering off, there should be a sensor so it doesn’t keep spinning in the socket, occasionally slipping out and hitting the floor. I worry about it breaking due to this. This thing arrived today and we couldn’t wait till Christmas to give it to our high play drive Australian Shepherd. It’s been barely above zero for weeks with no end in sight, and I have cold weather asthma so I really try to limit my exposure to the elements. Needless to say, my dog has been B O R E D. He truly craves interactive play with his humans, but last week I bought a cheap r/c cat toy that really caught his attention. So I splurged on this toy and so far, it’s AWESOME. He can’t control himself when the rope starts spinning. He pounces on it and it goes spinning off and around. He keeps picking it up thinking it’ll stop, but it keeps going. After 5 minutes of play he was acting completely gassed, but he just can’t resist it, as he put it down to get a drink of water and it started spinning again. Forget the water, I need that toy! As long as this thing can handle the teeth, slobber, dirt and grime, I’ll be a repeat customer!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on December 22, 2025
J
Verified Purchase
Jack H
Dallas, US
★★★★★ 4
My dog loves it...but needs charging four, five times a day. You really need 2 for full-time play
Color: Blue
My dog loves this toy. The first time she saw it and it started rolling, bounding, and waving the ropes around...she was barking at it, chasing it, grabbing it, jumping all over the place. There is no other toy she has that she will leave this for. And...that's part of the problem. I have to take this away from her three, four, five times a day to recharge it. The charge barely lasts an hour and the toy is dead. And it takes over an hour to charge it all the way up. Which means she plays with it less than it spends charging. That's not ideal. The product page and manual that comes with the toy says there is a 10-minute play period followed by a 30-minute interval to let the dog cool down...not get overly stimulated. I have never seen a cool-down period. I don't know if it's because the dog plays with it, shakes it around, tosses it and chases it, etc., etc., etc. constantly...but it just keep going until the battery is dead. I wish it did have a cool-down period. She likes playing with the ropes and rolling it around herself even after the battery dies, so if there was a cool-down, maybe it wouldn't need to be charged many times a day. Once it's charged and she sees me putting it back together, she gets very excited and starts jumping up and trying to grab it. Our corgi reduces most rope toys to threads in a day or less, and this one has held up surprisingly well against her super-chewing habits. The material the ball part is made of is very durable (we have a couple other toys with the same type of shell) and she's chewed on them all a lot without any damage. The toy keeps her entertained and happy...when it's not on the charger. I wish it was a good-enough value for the money to be able to justify buying two of them so I could have one charging while she was playing with the other. ================= I'm adding 1 star, because the company customer service is outstanding. They emailed me about my concerns vis-a-vis the short battery life, and it seemed that they really listened and cared about my input. I don't know what, if anything, can be done to extend the battery life given that it's spinning some substantial pieces of rope around, but I think they'll do as much as they can. In the meantime, my dog's love for this toy has not diminished in the least. She still gets very excited when she sees me starting to put it together after it's done charging, and she ignores everything else (sometimes even offers of treats) to play with it. I have a second one now, and I can almost keep them going full-time, but the few minutes every couple hours when both of them are on the charger is probably good for her anyway...she'd probably be over-stimulated if she had one of these to chase non-stop. Summary: Great toy, lots of fun, my dog loves it. However, you really need two the way things are right now unless you are okay with your dog being able to play less than half the time.
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Reviewed in the United States on March 13, 2026

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