CalMag Powder

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Designed to encourage rapid growth

CalMag is a readily available Calcium/ Magnesium supplement designed to encourage rapid growth, and reduce problems associated with Calcium/Magnesium deficiencies such as blossom end rot. CalMag is highly recommended when using RO water or coco coir media that lack the proper levels of Calcium and Magnesium to ensure vigorous plant growth.

Disclaimer: KEEP OUT OF REACH OF CHILDREN. NOT FOR INTERNAL USE. Avoid contact with skin and eyes. Irritates the skin, mucous membrane, eyes and gullet. Wear suitable protective clothing. Store at room temperature between 44 and 86 degrees Fahrenheit (7 and 30 degrees Celcius). Keep sealed and dry during storage.

Putting House & Garden Nutrients to the Test

Dr. Robert Flannery of Dr. Robb Farms compared different fertilizer programs in a real-world Cannabis sativa grow. The results showed that House & Garden’s dry and liquid nutrients helped produce strong, consistent yields—proven through science and experience.

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Key Benefits

  • Up to 30% greater yields (when used with H&G additives)
  • More cost-effective than other powders on the market due to concentration 
  • Customizable feeding program with the help of our professional grow consultants 
  • Compatible with commonly used biological additives

How It Works

  1. Use Rate: 1.4 –4 g (0.3 – 0.8 tsp) per gallon or 0.35 – 1 g (0.1 – 0.2 tsp) per liter
  2. Lower rates are advised for environments where light, temperature, humidity and/or air flow may be less than ideal
  3. Do not apply dry powder directly to growing media
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Grow Phase

Cuttings & Seedlings Vegetative Early Bloom Mid Bloom Late Bloom

Compatible Systems

Hydroponics Coco Soil
calmag powder 5 lbs bag

Guaranteed Analysis

Total Nitrogen (N) 12.0%

0.1% Ammoniacal Nitrogen

11.9% Nitrate Nitrogen

Calcium (Ca) 10.0%

Magnesium (Mg) 3.0%

3.0% Water Soluble Magnesium

Derived From:

Ammonium Calcium Nitrate Double Salt, Magnesium Nitrate