Product overview

Alga Grow

Algae-based nutrient for the growth phase

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Product information

Alga Grow is a basic plant nutrient that was created especially for soil-based cultivation. Alga Grow is used during the plant’s growth phase. This fertiliser, which is based on algae, aids in healthy and balanced growth and good root development. Alga Grow provides a sound foundation for the plant to flower profusely in a subsequent phase.

Dosage and use

Shake well before use. Add a maximum of 4 ml Alga Grow per 1 litre of water (1:250). Use this solution each time the plants are irrigated during the growth phase. For tailor-made advice, check our online Grow Schedule Calculator.

ATTENTION: This nutrient is not suitable for hydroponic growing systems. If you use an irrigation system, flush the pipes after use.


NPK fertiliser (4-2-4).


100 ml, 250 ml, 500 ml & 1 L bottle and 5 L, 10 L & 20L can.

Some sizes may not be available in all countries.

No, combined with our 100% NATURAL soils you don't have to regulate the pH and EC value of nutrient solutions.

No, this is normal and is not harmful for your plants. This is caused by the organic ingredients in Alga Grow. After the product has been dissolved in water, a natural bacterial process starts after a while. This causes the smell and can make your solution look cloudy. This does not have any adverse effects on your plants. If you have any questions about this, please contact us at

You can determine the shelf life by looking for the black batch number. Mail this number to the Plagron service desk ( They can tell you the best before date to use the product safely.

Yes, you can, once the mineral fertiliser is out of the substrate. With Lightmix that will take about a week, while with Growmix it will take about three weeks. As long as there are nutrients in the substrate, you'll have to monitor pH and EC values. You won't need to add nutrients. Once the pre-fertilisation is gone, you can start adding Alga Grow or Bloom and you won't need to monitor anything anymore. In the period between the two you'll only have to mind the pH. Alga Grow and Alga Bloom work perfectly well on 100% TERRA substrates. But Growmix and Lightmix are not organic and do not contain soil life.

Alga Grow

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Alga Grow is organic and certified by Control Union. This means that this basic nutrient is suitable for organic cultivation and is good for people, animals and the environment. Alga Grow improves the soil structure. It also has a positive effect on soil life through the presence of organic components, such as proteins and amino acids. This benefits the taste of the end product.

Alga Grow contains precisely the right amount of organic nitrogen. This stimulates steady growth. Nitrogen is one of the essential nutrients for the plant in the growth phase. It is important for the cell division and cell elongation of the plant, as well as for the creation of chlorophyll. In addition, nitrogen is important for the development of essential proteins and enzymes. These are all factors that are essential for the photosynthesis process.

Organic fertilisers need to be processed by the soil life into nutrients the plant can absorb. Alga Grow contains amino acids that simplify this process. This allows the plant to absorb nutrients more quickly, which in turn ensures faster growth. Alga Grow also contains amino acids that are directly absorbed by the plant, and serve as building blocks for essential plant proteins. These proteins are necessities for every imaginable process in the plant: they stimulate growth, increase leaf and fruit quality and encourage fruit development.

The algae extracts in Alga Grow are very important for the plant's resistance. They contain various organic molecules that have great added value for the plant. Such as growth stimulation, plant reinforcement and improved resistance to drought stress and temperature fluctuations.

In combination with one of our 100% NATURAL substrates, you do not need to adjust the pH and EC values of nutrient solutions. The pH-value is in fact adjusted automatically by the soil life in the substrate. This soil life is stimulated in this process by giving Alga Grow. After organic material is broken down by soil life, nutrients are released. As organic matter does not conduct electricity, the EC value cannot be measured.


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