Advantages and disadvantages, application and much more

the essentials in brief

• Clay granules consists of burned Clay balls(€ 22.65 at Amazon *) and can be used very well as a replacement for Potting soil use.
• Alternatively, you can also mix the material together with potting soil and thus improve the water storage capacity of the substrate.
• Clay granules have a very high water storage capacity, which is why you have to water cultivated indoor plants in them less often.
• However, there are some special features to consider when caring for these plants. Since clay granules do not contain nutrients, you need to regularly provide these plants with a special fertilizer.

What is clay granules?

Clay granules are literally granules made of clay

Clay granules, as the name suggests, are made from clay. This is a particularly fine-grained type of soil that is created by the decomposition of rock spades (again a collective term for various types of rock). Clay is considered a good water reservoir, a property that is further improved and optimized by the process of clay granulate production. To do this, clay is ground, granulated and then burned at extremely high temperatures of around 1200 degrees Celsius.

During this process, the organic substances contained in the raw material burn, producing carbon dioxide. The gas in turn expands the granulate so that the typical round spheres are created. Clay granulate has a porous surface and is therefore able to absorb and store water. For this reason, the material is ideal as a sole or additional substrate for indoor plants, but also for other purposes. What you can use clay granules for and what you should pay attention to is explained in the following sections.

Types of clay granules

There are different types of clay granules, which differ in these properties:

• Grit
• pH and salinity
• Suitability for plant species

Clay granules are available in different grain sizes, i. H. the beads vary in size depending on the product. A grain size of 4/8 is suitable for most indoor plants, as this is where the plant roots find the best hold - the small spheres with diameters between four and eight millimeters fill gaps well and leave little Cavities. However, they also only let a little air through, which is why you prefer to use a coarser grain size such as 8/16 for larger indoor plants.

There are also differences between the pH value and the salt content of the different products. Most clay granules have a pH of around 7 and are therefore suitable for most plants. On the other hand, those who need a slightly acidic substrate for their crops are well advised to use Seramis. With regard to the salt content, there are differences between the individual products between two and 920 milligrams per 100 grams of clay granules. If you put your houseplants in Hydroponics If you want to cultivate plants or species that are sensitive to salt, choose a product with less than 250 milligrams of salt per 100 grams of clay granules.

advantages and disadvantages

The most important positive property of clay granules is their ability to store water and gradually release it back to the plants as needed. Therefore, plants cultivated in this material have to be watered much less frequently. This table clearly shows the advantages and disadvantages of clay granules compared to conventional potting soil.

Digression

Which is why a water level indicator is indispensable when using clay granules

What can clay granules be used for?

Clay granules are probably the most frequently used in the care of indoor plants, which is why we are introducing three relevant areas of application to you at this point. But also in aquariums, terrariums, for Green roof or in pond construction there are various possible uses.

Hydroponics

With hydroponics, you only plant and care for your indoor plants in clay granules. For this, however, it is not enough to simply just dig through the potting soil Expanded clay(€ 16.35 at Amazon *) to exchange. On the one hand, switching to hydroponics requires careful washing of the roots so that no earth remains, on the other hand, you need special planting systems. These usually consist of an inner and an outer pot. In the inner pot you put the plant in the substrate, in the outer pot, on the other hand, is the water, which has to be topped up regularly together with the nutrient solution.

Conversion to hydroponics - that's how it works

The switch to hydroponics works as follows:

1. Pot out the plant.
2. Remove the earth. Rinse out any residues from the root ball.
3. If you shorten roots that are too long, brown (rotten) roots will also be cut off.
4. Pour a layer of expanded clay into the inner pot.
5. Put the plant on top and fill up the inner pot.
6. Lightly tap the bottom of the table to fill in any gaps.
7. Place the inner pot in the planter.
8. Fill in lukewarm water and don't forget the water level indicator.

Ball of earth in clay granulate - simplified hydroponics

It is less inconvenient to leave the root ball of the plants intact (and with soil). Instead, you simply put the plant to be repotted with the earthy root ball in a surrounding layer of clay granulate. Here the roots are practically embedded in the new additional substrate, but they are still in the ground. The water level indicator should not be missing here either.

Drainage for indoor plants - mix clay granules with soil

Mixing soil with clay granules saves watering

Alternatively, you can mix the clay granulate with the potting soil to improve its water-storing properties. to guarantee an optimal supply of moisture. You have different options:

• For pot drainage, pour a layer of expanded clay on the bottom of the pot.
• This should be between two and ten centimeters thick, depending on the size of the pot.
• First place a pottery shard over the drain hole so that it does not clog.
• Mix the potting soil with fine expanded clay balls.
• You will need about a handful for a 15 to 20 centimeter diameter pot.

A water level indicator is not absolutely necessary in this case, but it can make it much easier for you to determine the right time to water.

Digression

Broken clay granules for pond plants

Where can I buy clay granules?

You can purchase clay granules either as a branded product (e.g. B. Floragard, Seramis or Dehner) or as a no-name product (e.g. B. Own brands from DIY and garden centers such as Obi, discount store brands). Usual pack sizes contain between 2.5 and 50 liters of different contents, depending on what you intend to do. You can find larger quantities in special shops, such as those you need for waterproofing garden ponds.

frequently asked Questions

Is there a difference between expanded clay and clay granules?

The terms expanded clay and clay granulate both refer to burnt, reddish colored clay balls. So there is no difference in meaning between them, but there may be differences between them individual products and manufacturers - for example with regard to the grain size or the intended use. By the way, another name for clay granules is plant clay.

Can I completely replace the potting soil with clay granules?

Used correctly - as described in the article - clay granules can actually completely replace potting soil. Then, however, you have to pay attention to a few special features when caring for your indoor plants, such as the fact that using it alone without a water level indicator does not work or that you use them regularly fertilize have to. A simple finger test cannot determine whether the plants need water in the case of clay granules. Since the material is also inorganic, it does not contain any nutrients. These must be fed in continuously.

Are clay granules poisonous?

No, clay granules are usually not toxic. After all, it is a natural material that has only been burned and thus made structurally stable. Chemical additives are not added to most products. Nevertheless, you shouldn't eat the material, it's not intended for and would not be particularly good for you - your body cannot digest it. Instead, the globules could remain in the gastrointestinal tract and lead to serious blockages there.