CalMag & Iron contains an exact balance of calcium, magnesium and chelated iron specially formulated to compensate for insufficiencies that are sometimes encountered – particularly in some commercial and hydroponic nutrient programs and grow mediums. CalMag & Iron is compatible in all grow mediums and compensates for the natural calcium draw of coco coir fiber and may be needed for those growing with reverse osmosis water.
How To: Use CalMag & Iron at a usage rate of 2-5ml/gallon. CalMag & Iron can be used as a soil drench or foliar spray and is compatible in all mediums.
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Liquid (ml/l)
N-P-K / Micro-elements Nutrient
Non-Organic
Day-to-day Solution
Humboldts Secret Product Line
Take a look at complimentary nutrients which are also available from Humboldts Secret. These products will compliment each other, or serve different purposes.
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