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Emerald Harvest Cal-Mag

Product Code: HYV-0488
Cal-Mag is the ultimate addition to growing in coco. Use in harmony with your favourite PK fertiliser to replenish essential calcium and magnesium and prevent nutrient deficiencies.

Emerald Harvest Cal-Mag

Cal-Mag is the ultimate addition to growing in coco. Use in harmony with your favourite PK fertiliser to replenish essential calcium and magnesium and prevent nutrient deficiencies. 


Replenishes calcium lost in coco

Coco coir is a rich source of potassium, but it’s important to supplement the macronutrients that it’s less kind to. Bright grow lights or rapidly-growing plants are prone to magnesium deficiencies. It’s one of the key components of chlorophyll, which keeps leaves green and strong and is vital for photosynthesis. Coco substrates have a reputation for holding onto calcium and making it unavailable for plants to use, so a calcium supplement is always recommended. 


A little help from kelp

As well as these important secondary nutrients, Cal-Mag contains kelp extract for a boost of natural goodness. Kelp is known to fortify the structure of plant cells and stimulate shoot growth, making it especially useful in the vegetative stages. It’s a biostimulant that increases plants’ ability to draw available nutrients from the substrate.

Young plants will show increased tolerance to stress and develop strong, robust roots and shoots in early growth. 


How to use Emerald Harvest Cal-Mag?

Cal-Mag has no specific feeding routine: apply as needed from the early vegetative stage through to late flowering. It is recommended for use on watering days only. 

Depending on your growing medium and plant necessity (showing signs of calcium and magnesium deficiency, for example), growers should dilute between 0.5ml and 1.25ml of Cal-Mag per litre of nutrient solution. 

Do not use Emerald Harvest Cal-Mag in conjunction with Emerald Harvest Sturdy Stalk


Where to use Emerald Harvest Cal-Mag?

Emerald Harvest Cal-Mag is particularly beneficial in coco-grown plants, since coco coir is known to retain calcium and make it inaccessible to plants. 

However, it is a soluble liquid nutrient and will provide safe, effective results in any growing medium, including in soil and in hydroponic systems, tanks, and reservoirs. 

Cal-Mag may also be diluted and used as a foliar spray. However, it is recommended that you do not apply other products directly before or after as this may lead to issues with mould and/or mildew. 


Why choose Emerald Harvest Cal-Mag?

  • Supplements secondary nutrients calcium and magnesium;

  • Prevents yellowing and brown spots;

  • Replenishes the calcium lost in coco growing;

  • Can be used alongside other nutrients;

  • Contains nitrogen for protein formation;

  • Available from 0.95L to 22.71L. 


Product Specifications:

  • Brand: Emerald Harvest

  • NPK Ratio: 2 - 0 - 0 (Nitrogen Content: 90% Ammoniacal Nitrogen, 10% Nitrate Nitrogen)

  • Other Active Ingredients: Calcium (3%), Magnesium (0.5%)

Product Data

  • Brand: Emerald Harvest