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
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
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Exchange/Return Notes
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  • Final sale items are not eligible for returns or exchanges.
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SKU: 78922371987

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TIM
Alexandria, US
★★★★★ 5
Thamks
Size: 5FT, Style: 8AWG
Thanks
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Reviewed in the United States on October 9, 2025
D
Dave B
Houston, US
★★★★★ 5
Very high quality wire is great for automotive use
Size: 25FT, Style: 8AWG
This is really good quality wire. The insulation is thick, it is super flexible and very finely stranded. In fact the strands are so fine that you really should be using ferrules to terminate the wire. Without a ferrule, it would be very easy to have a stray strand extend to another terminal, and the strands are so fine that you may not even see it if you have old eyes like me. I used this wire to run from my battery to a fuse, and then to an amplifier inside my vehicle. The wire is so flexible that it may be difficult to push it through the grommets in the firewall of a vehicle. I wound up taping it to a coat hanger, and pushing it through, which was an effective workaround. The insulation is also a bit grippy, so it may be a good idea to apply a lubricant to the grommet, so you don't wind up pulling the whole grommet out of the hole while pulling the wire. If I needed more wire, I would certainly pick up more of this for my next project.
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Reviewed in the United States on October 14, 2025
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Oldshoes
Battle Creek, US
★★★★★ 5
Good as it Gets
Size: 50FT, Style: 8AWG, Size: 50FT, Style: 8AWG
This is excellent wire I've been doing solar set ups for about 2 years now and this is as good as any I have used or seen. The Silicone insulation is super supple - it can easily be bent into quarter (25 cent) size loops. It is a true 8AWG super fine stranded tinned copper cable. It doesn't appear to be listed - but the cable is stamped every couple inches with 200* C and 8AWG. I'll forgo the listing - I know this stuff is good wire - and the only inspection I have to pass is my own. I ordered the 50 foot Red, 50 foot black. It is selling now for about 90 bucks. 90 cents a foot – pretty good deal for this wire. 7 Super Novas for The YDDECW 50ft Red & 50ft Black, 8 AWG Tinned Copper cable kit.
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Reviewed in the United States on August 31, 2025
G
Gabe
Birmingham, US
★★★★★ 5
Flexible and bendable
Size: 50FT, Style: 8AWG, Size: 50FT, Style: 8AWG
The 8 Gauge Silicone Wire kit (50ft red and 50ft black) is an absolute game-changer for anyone working with RC cars, boats, drones, or any high-performance electronics! The wire is made from 1650 ultra-fine tinned copper strands that offer incredible flexibility and bendability. This makes it perfect for tight spaces or projects that require a lot of maneuverability. The silicone insulation is top-notch—it's soft, durable, and incredibly heat-resistant, handling temperatures from -60°C to +200°C without issue. I’ve used it in various applications, and it’s been flawless in both scorching heat and freezing cold conditions. Plus, the tinned copper core ensures excellent conductivity and low resistance, which means maximum efficiency for your devices. Whether you're wiring RC planes, boats, cars, or working on home appliances or motors, this wire has you covered. It’s also eco-friendly and non-toxic, which is a huge plus if you care about the environment. The kit includes 50ft of red and black wire, which is more than enough for most projects. If you're looking for durable, flexible, and high-performance wiring that can withstand extreme conditions, this silicone wire is the way to go! Highly recommend it for anyone in need of reliable, long-lasting power solutions for their electronic projects!
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Reviewed in the United States on August 1, 2025
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EternianUber
Waukegan, US
★★★★★ 5
Nice unit
Set name: 5.1 Receiver
I'm really happy with this receiver even though I don't have any speakers hooked up to it. Not using it for a speaker setup might sound like a waste of a product to some people but honestly I'm finding plenty of value in it with it's other features. The main reason I looked into getting a receiver was so I could have multiple hdmi devices hooked up to my monitor. I looked into hdmi hubs but there are a couple reasons why I've chosen a receiver instead. 1. Reliability and ease of use. Ok, so like I said I use a monitor in my room, not a tv. Monitors don't have remotes so anytime I want to change the volume or hdmi input I have to do it manually. It's a 32 inch monitor about 3 feet to the side of my bed and it's a nice arms stretch to do so. Not a big deal and while there are plenty of hdmi hubs that offer remote changing or automatic changing I worry about the reliability of those devices. There are plenty of reviews that state their hubs stop working after some months or the automatic hdmi switching starts changing inputs randomly or getting black screens and such. I just didn't want to hassle with things like that. 2. Bluetooth connectivity. This was another feature that I was looking into. Again, there are separate devices that offer this but just like hdmi hubs you will find plenty of reliability concerns. On top of that there's audio lag and previously when I bought a bluetooth transmitter I had to return it for that reason. Nice thing about this receiver is there is an adjustment for the audio to increase or decrease the audio timing but luckily it isn't an issue and the audio seems to be timed perfectly with my bluetooth headphones. It pairs up quickly too. I haven't tried the 4k upscaling with this receiver because I use a 1440p monitor but it's nice to know that it's there. Maybe in the future I will find a use for it. There's also some neat audio presets for things like movies, music and gaming. It's actually a pretty extensive list. I suppose I should also mention that each hdmi input can be named to your liking for a nice customization feel so when you flip through them you know exactly what's connected to that input. You can even use the hdmi ports when the unit is in standby mode but you won't be able to use the bluetooth connectivity. In the end I think this was a good purchase. It's priced reasonably and I'm getting good use out of it. Sound quality is great and the customizable features are a definite plus. More expensive than getting an hdmi hub and bluetooth transmitter but I think the reliability and extra features make up for this.
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Reviewed in the United States on July 23, 2019

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