© 2023 ~ Cold War Organics
potting media parameters

This table is a general guideline. There is a wide range of values in the ADEQUATE column but, for younger plants, we recommend that you keep nutrient levels at the lower end of the adequate range. To amend your potting mixture, see our Calculation Forms.

PARAMETER UNIT LOW ADEQUATE HIGH
pH (less than 20% soil) <5.5 5.5-6.8 >6.8
pH (more than 20% soil) <6.0 6.0-7.0 >7.0
EC (Conductivity) for mature plants ms/cm <0.7 0.7-3.5 >3.5
EC (Conductivity) for young plants ms/cm <0.5 0.5-2.0 >2.0
Available Nitrogen (ammonia + nitrate) ppm <40 40-200 >200
Phosphorus (less than 20% soil) ppm <5 5-25 >25
Phosphorus (more than 20% soil) ppm <2 2-18 >18
Potassium ppm <50 50-150 >150
Calcium ppm <50 50-200 >200
Magnesium ppm <20 20-150 >150
Sodium ppm 0-80 >80
Sulfur ppm <20 20-200 >200
Boron ppm <0.5 0.5-2.0 >2.0
Iron ppm <10 10-40 >40
Manganese ppm <5 5-30 >30
Zinc ppm <5 5-30 >30
Copper ppm <0.5 0.5-10 >10

– Cold War Organics –

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Warmheartedly Ground, Rolled and Packed in New England.