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Roots Organics CalMag




Roots Organics CalMag is a pure and all-natural blend of calcium, magnesium, and sulfur to support plants during fast growth. Use Roots Organics CalMag as a calcium and magnesium supplement to adjust to the needs of various mediums and growing conditions.

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HTG Supply is committed to providing you with the very best products, pricing and service in the industry. We will ship your order fast and discreetly packaged to protect your privacy. Buy with confidence knowing your HTG Supply purchase includes simple returns as well as lifetime product support. Call our team of real growing experts with your purchasing or product use questions, and we will be here to help!

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Roots Organics CalMag

The long-awaited Roots Organics CALMAG provides a big kick of liquid calcium and magnesium and a healthy percentage of sulfur, a frequently overlooked component of flowering fertility needs. By creating a product without added nitrogen, phosphate, and potassium, we give you control to supplement as needed without influencing primary fertility input ratios. This makes CALMAG the best possible natural calcium magnesium flowering supplement for organic crop production.


Calcium 4.0%
Magnesium 1.0% (0.5% Water Soluble Magnesium)
Sulfur 4.0%

Kieserite, Gypsum


Seedlings and small plants
Use 1 teaspoon (5 ml) per gallon.
Mature vegetative plants
Use 1 – 3 teaspoons (5 – 15 ml) per gallon.
Mature flowering plants
Use 2 – 3 teaspoons (10 – 15 ml) per gallon.