SKU: 23500156424
cal mag for pot plants

cal mag for pot 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

cal mag for pot 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.


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4.8 ★★★★★
Based on 30 reviews
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Product Reviews
B
Verified Purchase
Brock Isaacks
Chelsea, US
★★★★★ 5
Bass Forward, Heavy physicality, Excellent upgrade!
Color: Blue, Color: Blue
I would like to start this by saying that I’m having to rewrite this as my first one violated community guidelines so I guess. But I wanted to preface that I have owned at least 1 of every generation of the JBL Boombox Series (1 OG BB, 2pair Gen 2, 2 pair Gen 3, 2 for the current JBLboombox 4!! I’m also extremely into audio and technology and speakers are an expertise of mine! I personally think that this was the biggest leap forward in the series and although I am still disappointed we reverted back to a 2-way system instead of the pioneering 3-way set up and that is a bummer but as far as feeling the music, want bass? Can’t get enough. These Boombox 4 CRANK that low Freq and can sustain a sub 40 Hz base note on battery for extended periods of time. I had no idea that physics would allow such a small item to create base like it does and that’s given proper acoustics of the room of the hallway ~~you know, you put your speaker somewhere and you’re like it sounds the best right here. That’s the soundstage (ish) but wow! The two base boost options are awesome and remind me of the OG BB with what was called “home and outdoor mode” When I’m rocking my stereo pair of Boombox 4s I basically always have the bass boost feature turned on the deep base (mode 1) and the other option (mode 2) is to have “punchy base” however I don’t recommend that one. Overall super happy with Bluee & Squad box! I will say that the only lighting feature on it is to me a very useful and fun incorporation of LEDs into a portable speaker as the color whether orange or white will show you from a distance what bass mode you’re in but also, you can verify it by a glance and rockin’ these dark orange glows, white punches or nothing at all. :) Oh and the Original JBL I got in 2017 is still working like a charm in a buddy’s garage of mine (battery is shot, must stay plugged in to use) But JBL will last a long time, there’s such a big variety to choose from on the Bluetooth market these days that you can find a speaker for any size occasion or prefer preference. Lastly…✅✅✅✅ AURACAST ✅✅✅✅HAS BEEN FLAWLESS!! 🤩 as I had connection issues with every type of linking JBL’s had to offer since Connect… so JBLs Connect, Connect+, partyboost, ect ….. no good! ESPECIALLY in a dang stereo pair. Now when I turn on both speakers, they automatically link into stereo mode and it is simple as can be and they haven’t even hiccups once for the hundreds of hours they’ve played music already. Well I hope this finds someone who I intent it too, That’s all folks!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on December 18, 2025
E
Verified Purchase
Eugene Sandow
Lowell, US
★★★★★ 5
I ran out of stars!!!
Color: Blue
It's hard to know where to begin when talking about the JBL Boombox 4. Let me begin by stating I'm no stranger to JBL speakers of which I have several. I've had 3 extremes, 2 charges, and 1 Big Boombox #1. This boombox 4 is another beast all together. Let me also add I'm also a recording/ mixing engineer so I have pretty good ears for music and how things should sound. I was literally overwhelmed by the sheer size and essence of the BB4. It was like trying to take control of a baby elephant that had somehow gotten loose. It almost seems twice the size of the Boombox 1-3 but it is fatter around middle which gives it a chunkier appearance. It really is a beauty to behold especially in blue like mine. The sound is better than the others but to get that fat bass you have to push the bass (B) button to the first level. Push it again and bass as well as vocals and instruments are pushed more to the forefront and more in your face. I don't play music loud and usually stick with smooth jazz styles. Everything I've played has sounded good with the bass button engaged. I can only compare the BB4 to the BB1. The BB1 is still very good with good bass response but the BB4 blows it out of the water. I could've lived with the BB1 but I know one day the battery is going to die and I'd be stuck with a very large door stop. I refuse to go through the stress of trying to replace the battery in another JBL speaker which was pure hell and it still never worked again. When I heard about the new batteries and how easy you could swap them out I was sold. I almost got the extreme 4 but the Boombox 4 had a much bigger and expansive sound. Reviewers have reported that the stereo spread is non-existent. Not true. I hear very good stereo separation. Not exactly as wide as two separate speakers but very good as it is. I really didn't need another speaker especially one so pricey but the ability to easily remove the battery says this speaker will be around for a very long time. At this price point the speaker case could and should have been included with the purchase.
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Reviewed in the United States on November 11, 2025
D
Verified Purchase
DeAngelo D.
Waukegan, US
★★★★★ 5
Quality requires no 2nd thoughts
Color: Black, Color: Black
🙋🏾‍♂️I’ve owned the original BoomBox 1 since 2019. I had that battery and brick replaced in February of 2023 and that thang never lost any of its sound quality over that 4yr period. Sadly those replacement items just gave out on me on February 3,2026. I contemplated replacing the battery and brick once again because the speakers were still grade A in sound quality…but then I saw the Boombox4 and thought,”why spend another $200 when I’ve already done so?” I paid $499 for Boombox1 so I wasted no time ordering Boombox4 and I’m thrilled to see that the engineers have designed the 4 without a brick and that it’s charging system automatically shuts off once it reaches 100%. This was the only issue I had with the original Boombox1 and now I look forward to YEARS of usage. I’m a FedEx courier with a rual route and I spend 12hrs a day out there on the road! JBL Boombox4 has no issues keeping up with my demands…just like the original. Come to think of it,I’m going to get the battery and brick replaced on the Boombox1 and keep it as well,salute JBL…I am your #1 supporter ✊🏾🖤
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Reviewed in the United States on March 2, 2026
E
Verified Purchase
Exceptional Quality & So light More than i could have dreamed of
Alexandria, US
★★★★★ 5
REAL PHYSICAL SUBBASS
Color: White
You can actually physically feel the bass. The bass boost 1 mode is super super amazing its sound quality parallels the JBL Ultimates which i have 2 of and this color is marvelous. The weight is also amazing my infant daughter loves this speaker and I'm soo soo impressed on the progress the boom box has made in the past 5 years this version completely outshines previous generations. LOVE IT!!
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Reviewed in the United States on June 7, 2026
T
Verified Purchase
Thomas C.
Charlottesville, US
★★★★★ 4
Badass speaker🔊
Color: Black
It’s one powerful speaker. 🔈 I’ll have to do another survey after I use it for a couple day I’ve only turned it on once for only 10 minutes but so far so good
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 4, 2026

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