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Product information

Plagron Promix is a mix of the very best, carefully selected types of peat. The addition of various types of fibre results in a lightness and oxygen level found only in Plagron quality substrates. No nutrients have been added to Promix, only Plagron worm castings. The worm castings stimulate the growth of soil organisms and activate the organic fertilisers which have to be added as from the first day. This makes Promix the perfect potting soil to fertilise organically according to your own judgement and choices. The result is a 100% organic yield. Promix produces the highest yields when used with Plagron Alga Grow, Alga Bloom and the additives from Plagron.


Start fertilising the first day with for example Alga Grow.


Peat, worm castings.

pH 6.5 - 7.9 
EN13037 pH (H2O)

EC 0.5 - 0.8
E.C. (1:1.5) [mS/cm]


50 L bag.

Some sizes may not be available in all countries.

You should start adding nutrition from the first day. Start off with Alga Grow and switch to Alga Bloom later. More information about dosage and type of base nutrient can be found in our Grow Schedule.

According to the 100% NATURAL Grow Style you don't have to regulate the pH and EC value of nutrient solutions when you combine Promix with Alga Grow and Alga Bloom.

Yes, technically this is possible. However, the airiness of Promix will make it difficult for the seeds or cutlings to absorb moisture. Therefore they will not develop as well and less quickly. The fibers in Promix also may hinder the seeds when they are growing out of the soil. Therefore you should rather use our Seeding & Cutting soil.

Seeding and Cutting Soil has a low EC value. This promotes the germination and rooting of young plants. The fine structure of Seeding and Cutting Soil ensures that roots can develop optimally.


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Because no nutrients are added to Promix, it is suitable for the more experienced grower. You are directly in control of the fertilisation. So start fertilising from day one with our organic growth nutrient Alga Grow.

Promix has a low EC value since it is not pre-fertilised. This is ideal for young plants, because they will experience little stress. Your plant can root quickly and therefore has a healthy basis for stable growth.

Promix is organic and certified by Control Union. This means that this substrate is suitable for organic cultivation and is good for people, animals and the environment. Promix is not pre-fertilised, contains a high organic content and is rich in soil life thanks to the added worm humus. Add organic nutrients from day one to support this soil life and your plant will grow and bloom naturally. This will benefit the taste of the final product.


Want to know where to buy this product? Or perhaps you’re looking for a custom schedule or just a helping hand? Our Tools have got you covered.

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