Potting soil substrates

We are all familiar with potting soil and to the untrained eye, everything appears to be the same. Supposedly and often heard: “heap of dust”, dredge. Fortunately, I can say that it is a lot more than that.

A grower wants to grow the most beautiful and best plant. Ideally, everything should be ready for sale at the same time as much as possible. That means: uniformity, good colour, a strong plant that is stable in the pot, sufficient buffer in the pot for the sales channel and much more. After all, that cultivated plant represents the pride and skills of his work.

This is all influenced by what happens in the ground and what takes place above ground. Often, we pay attention to everything that is "easy" to see. This is easily and quickly visible, but when negative signals are visible, the suffering may have occurred days or weeks earlier. All aspects of plant cultivation must therefore be properly secured, and potting soil is an essential component of this.

Potting soil or substrates are frequently a blend of organic and inorganic components.

Peat particle, organic substrate

Organic component
This includes various types of peat, peat that is milled or peat from peat or blocks. However, there are also other organic components (read: additives) such as Perlite ('popped' volcanic rock), Pumice stone, clay granules, vermiculite, sand, compost, clay, coconut and coconut fibre, wood fiber and pieces of tree bark (pine). Each component has its own characteristic pH and EC value as well as air content* and water content*².

Inorganic component
We are mainly talking about stone wool products.

Each component has its own set of physical and chemical characteristics. In this way, we can determine the total properties of a potting soil composition, which can influence the growth and development of a plan. By adding clay, for example, the water is fixed, and the plant must expend more energy to separate the water from the clay complex. As a result, the growth is compact.

Of course, a number of basic fertilizers should be added to the potting soil mix at the start of the cultivation. This can be determined through careful consultation. The pH and EC are determined based on the crop, and a starting fertilizer (NPK) and amount of lime are added in accordance with advice. Flowers and plants have unique nutritional requirements in order to grow and develop properly. For example, a Pelargonium has a relatively high nutritional level, while a Phalaenopsis has a low nutritional level.

Slow-release fertilizers can be chosen, these are effective for a number of months to approximately 18 months. These types of fertilizers are often used in tree nursery.

There are of course several options. Experience has shown that a large proportion of plants can meet with some standard mixture. If you would like to know more about the potting soil we offer or a composition, please contact us or use our substrate request form here


Air content: percentage (%) of air in the volume / substrate.
*² Water content: percentage (%) of water that is maximally absorbable in the volume/substrate.