How to use grow mats?

Because the growing slab as an inert medium can be used excellently in a planter and also with drip irrigation within a hydroponic system, let’s now briefly focus on the TOP growing slabs on the market and their practical use.

Cocos Slab (Plagron)

These growing slabs for plant cultivation are made from coconut fibers (besides the Cocos Slab, for example also the UGro Slab - compressed slab). Compared to the mineral-origin slabs listed below, they stand out primarily for their 100% natural composition and meet the strictest quality standards (RHP).

When using the one-meter growing slab Cocos Slab from Plagron, proceed as follows:

1. Shake well before use, but do not rinse. The substrate is ready for immediate use.
2. Just check that the drainage holes at the bottom of the Cocos slab are large enough.
3. Place the plants into the Cocos slab.
4. pH of the water adjust to 5.5.
5. An advantage of this growing slab from Plagron is that it itself ensures low levels of EC.
6. For feeding plants grown in growing slabs, consult the dosage charts directly from the manufacturer. The Cocos Slab slabs are truly a perfect medium for hydroponics. If you decide to use them, we recommend combining them with the two-part nutrient from the same brand, i.e. Plagron Cocos A+B and also with additives Power Roots, Pure Enzymes and Green Sensation.
7. The substrate itself contains no fertilizers, so the above nutrients can be dosed according to the dosage charts from day one. However, the substrate does contain the beneficial fungus Trichoderma, which positively influences the healthy development of a strong root system by surrounding and effectively protecting it, for example against mold infestation.
8. These growing slabs from Plagron can also be reused. That is, besides their purely organic origin and composition, their main advantage compared to Grodan slabs (see below). You will know it’s time to replace the growing medium after several months by the measured value of EC, if it is higher than 1.8, or the pH, if it is lower than 5.4 or higher than 6.5. Everything for measuring pH and EC can be found HERE.

Classic, Master, and Expert (Grodan)

• Growing slabs from Grodan have a mineral origin. They are made of horizontal fibers of quality basalt wool (rockwool), which slightly raises pH.
• As an example, we can mention the best-selling Grodan Master with various densities of hydrophilic fibers. Compared to the Classic or Expert slabs, we observed better water and nutrient management with the MASTER slab.
• These growing slabs provide a balanced ratio of water and air. They are firm yet airy, increase plant oxygen uptake and nutrient absorption, and maintain stable pH. They also ensure uniform plant development across the slab. Furthermore, they allow full control over the electrical conductivity values of the solution. Because of this, they are considered by growers to be one of the most popular growing media for hydroponics.
• We recommend using one growing slab for only one cultivation cycle!
• You can use them alone, but also as a practical base for rockwool seedling cubes.
• Rockwool should be soaked before use in lukewarm water at about 25 °C, preferably already with the pH adjusted to the range 5.8 – 6.

COGR - compressed slab (Canna)

A separate chapter among growing slabs is the Canna COGR - compressed slab, made from a special mix of coconut husks, fibers and coconut granulate, which will satisfy even the most demanding hydroponics enthusiasts.

• This inert substrate from a prestigious manufacturer is simply a clear guarantee of maximum aeration and absorption of nutrients and moisture!

• Just like the slabs from Plagron, you can also use Canna COGR repeatedly - even up to three times in a row, and moreover without the slightest loss of quality.
• It is important to first moisten the compressed sheets using the special COGR Buffering Agent. Then it is necessary to fertilize with COGR Vega during the vegetative phase and switch to COGR Flores in the flowering period.
• From a practical usability perspective, part of these growing slabs can be crushed and divided into any pots. So you don’t have to limit their purchase only to planters and hydroponic systems.

If you are involved in hydroponics and have not yet tried growing slabs, maybe now is the time to fix that. If you have any questions, we will be happy to answer them at the usual address info@higarden.cz.

We also recommend these products:

• Plagron Cocos A+B (from 329 Kč): a two-part plant nutrient ideal for cultivating plants in Cocos Slab.
• Hydroponic planter Libra (199 Kč): designed for both coconut and rockwool growing slabs.
• pH and EC meters (from 99 Kč)

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