

🌱 Elevate your garden game—because your plants deserve the VIP treatment!
Botanicare Cal-Mag Plus is a premium liquid plant supplement delivering a potent 2-0-0 NPK formula enriched with calcium, magnesium, and iron. Designed to correct common nutrient deficiencies, it supports healthier, greener plants whether used in soil, coco coir, or hydroponic systems. Easy to mix or apply as a foliar spray, it boosts growth, strengthens stress tolerance, and integrates smoothly into any nutrient program.










| ASIN | B004JKBMRW |
| Best Sellers Rank | #2,820 in Patio, Lawn & Garden ( See Top 100 in Patio, Lawn & Garden ) #108 in Garden Fertilizers |
| Brand | Botanicare |
| Customer Reviews | 4.7 4.7 out of 5 stars (22,457) |
| Global Trade Identification Number | 00783942912227 |
| Is Discontinued By Manufacturer | No |
| Item Form | Liquid |
| Item Weight | 8 ounces |
| Item model number | HGC732110 |
| Liquid Volume | 946 Milliliters |
| Manufacturer | Hawthorne Hydroponics, LLC |
| Number of Items | 1 |
| Product Dimensions | 5.1 x 2.3 x 7.3 inches |
| Specific Uses For Product | Plant Growth, Root Development, Soil Conditioning |
| UPC | 714639456878 757900240325 783942912227 |
| Unit Count | 32.36 Fluid Ounces |
R**K
Great product as always
I recently added Botanicare Cal-Mag Plus to my plant care routine, and I’m really impressed with the results. The product arrived promptly and was excellently packaged, with no leaks or damage to the bottle, which is always a relief when ordering liquid supplements. From the first use, it was clear that this supplement was high quality. It’s easy to measure and mix with my regular nutrient solution. I started using it a few weeks ago, and my plants have shown significant improvement in their overall health and vigor. Cal-Mag Plus is fantastic for addressing common deficiencies in calcium and magnesium, which are crucial for plant growth. Since incorporating it into my routine, I’ve noticed my plants’ leaves are greener and more robust. There are no more signs of yellowing or other deficiency-related issues. This has been particularly beneficial for my tomatoes and peppers, which are heavy feeders and often prone to such deficiencies. Another great aspect of Cal-Mag Plus is its versatility. I use it for both my soil and hydroponic plants, and it integrates seamlessly with my existing nutrient regimen. It doesn’t cause any imbalances or issues, which makes it very convenient. I’ve also observed that my plants are more resilient to stress since I started using this supplement. They seem to handle fluctuations in temperature and light better, and their overall growth has been more vigorous. The added iron in the formula is a nice bonus, contributing to better chlorophyll production and healthier plants. Overall, I’m extremely satisfied with Botanicare Cal-Mag Plus. It’s a reliable, high-quality supplement that has made a noticeable difference in my plants’ health. If you’re dealing with calcium or magnesium deficiencies, or just want to ensure your plants have everything they need to thrive, I highly recommend giving this product a try. It’s become an essential part of my plant care routine, and I’m excited to see continued improvements as I keep using it.
N**Y
Works
Just the right supplement I needed. Solved my growing problems.
F**S
Good mix for your grow
You can do without a lot of what they sell to indoor growers. This, like a good fertilizer, is imperative. Bottle was well sealed with no leakage. I use 50ml plastic syringes (no needle) to get an exact mix. I've been using this for years and see no reason to quit.
B**R
Great product but packaging has terrible design
The product does what it's supposed to do, but you'll have to find a way to manage the spillage since they didn't bother to do so when they designed the bottle. I usually have more runoff down the side of the bottle and drippage off the bottom of the bottle than what I need to use per feed. I've had to pour way more than I need into a bucket, scoop it with a teaspoon, and pour the remainder back into the bottle.
R**N
Such an important product
This product seriously helps! If you grow cannabis, you need to buy it!
S**R
Tomato’s are happy/ I’m happy
Tomatoes need calcium. Mine just started to show that tell tale sign of deficiency and they straighten right up and had a wonderful year. Gave them a few doses and backed off. Then a few more about 12-14 days later. Caught it early. Very grateful for this helpful product. Easy to mix , strength was excellent. . And a decent value for the return .
M**W
The "Insurance Policy" for Your Garden
Whether you are a hobbyist with a few houseplants or a professional managing a high-output indoor garden, if you are using Reverse Osmosis (RO) water, Coco Coir, or high-intensity LED lighting, this isn't just an "add-on"—it’s a necessity. Here is the professional breakdown of why this 2-0-0 formula is the gold standard. The Engineering: The "Plus" Makes the Difference Most calcium-magnesium supplements stop at the two namesake minerals. Botanicare’s "Plus" refers to the inclusion of Iron (Fe) and other trace minerals. The Iron Factor: In my 10 years of testing, I’ve found that yellowing leaves (interveinal chlorosis) are often misdiagnosed as just a magnesium deficiency when they are actually an iron lockout. The chelated iron in this formula acts as a catalyst for chlorophyll production, giving your plants that deep "forest green" luster that basic supplements can't match. Bio-Availability: This is a highly soluble, plant-available formula. It doesn't "fall out" of solution or clog emitters in hydroponic systems, which is a common failure in budget-brand minerals. The Versatility: Root Drench vs. Foliar Spray The CT-1's flexibility is its greatest asset. Root Feeding: It buffers the "cation exchange" in Coco Coir perfectly, preventing the medium from "stealing" calcium from your plants. Foliar Rescue: This is the "fast-track." If you see a deficiency starting, you can dilute this as a spray. Because it’s so clean, the leaves absorb it almost instantly, often reversing yellowing in as little as 48 hours. PROS Highly Concentrated: A little goes a long way. The standard dose is only 3–5ml per gallon, meaning this quart will treat hundreds of gallons of water. Corrects "LED Stress": Modern LEDs drive plant metabolism so hard that they often "burn" through calcium and magnesium faster than the base nutrients can provide. This bottle is the solution to that specific 2026 growing problem. Stabilized pH: Unlike some organic-heavy supplements, Cal-Mag Plus is relatively pH-neutral, so it won’t cause wild swings in your reservoir. Universal Compatibility: It works seamlessly with any base nutrient brand (FoxFarm, General Hydroponics, Advanced Nutrients, etc.). Clean Formula: It won't cause "salt crust" buildup on your fabric pots or in your irrigation lines. CONS The 2-0-0 NPK Warning: It contains a small amount of Nitrogen. If you are in the "late bloom" or "ripening" stage of a flowering plant and trying to zero out your nitrogen, you have to be careful not to over-apply this. Not for Low-Light Plants: If your plants are in low-light conditions, they likely don't need this level of supplementation. Over-applying can lead to "nutrient burn" in slow-growing species. Price: It is priced as a premium product, but given the concentration and the included iron, the value is actually superior to "cheap" alternatives. Overall Input Botanicare Cal-Mag Plus is the most reliable tool in my garden. It solves the #1 problem in modern gardening: mineral deficiencies caused by purified water and high-intensity lights. It is a rugged, scientifically sound, and battle-tested formula. If your leaves are turning yellow or your fruit is getting "blossom end rot," this is the cure. Reviewer Pro-Tip: If you are a Coco Coir grower, you should "pre-buffer" your medium with a half-strength solution of this before you ever plant. Also, if you’re using it as a foliar spray, apply it when the lights are about to go off or in the early evening. This prevents the "magnifying glass" effect of water droplets burning your leaves under intense light! Who is this for? Hydroponic growers, Coco Coir enthusiasts, LED indoor gardeners, and anyone struggling with yellowing leaves or stunted growth in their house or vegetable garden.
S**S
Does what is says on the bottle! No gimmicks required. Excellent product!
I**Y
I’ve been using this product for years, and it has never let me down. Not once have I had blossom end rot on my tomatoes since I started applying it. It simply works exactly as it should, and I consider it a must-have for a healthy garden. My only gripe is the price—it’s gotten pretty steep on Amazon compared to what I can find it for locally. Still, the product itself is five stars all the way. If you’re serious about preventing blossom end rot, this is a no-brainer.
A**A
Love in it
W**Y
Accidentally caused calmag deficiency in one of the plants by dropping pH too much, so I applied this by mixing it into daily water plus spraying it on leaves (diluted as per instruction of course). It only took a bit over a week for the new leaves to regained deep green colour. I'm sure I overpaid a bit by order it online, but overall very happy with the product.
H**A
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