How to choose Professional LightTer Growing Medium?
The entire range of substrates Fertil – DSP is designed and structured according to the characteristics of the constituent materials.
It follows, that the choice for cultivation must be carried out according to the same criteria. In other words, you should not choose the medium according to the specific crop, but according to the specific method of cultivation adopted.
What does “physical properties” mean?
For physical properties of the substrate, we mean characteristics determined by the spatial distribution of the solid particulate , by its size and its nature.
The physical properties are of fundamental importance, because they provide valuable guidance on the most suitable irrigation method, on the better container size.
To navigate the contents of the Product Data Sheets or the of our dedicated handbbok You must have understood some concepts and notions concerning physical characteristics of the growing media.
Which are the main physical properties?
Dry bulk density (bulk density):
It expresses the dry weight of a known volume of soil. It is a density refered to the material dried at 105 ° C and not to the wet medium. The value of the dry bulk density provides valuable information on the composition and physical structure of the mixture;
Volume of water at pF1 and pF2:
The amount of water available for plant uptake in a peat growing medium is comprised between two values of suction force (force exerted from the roots in the water absorption and analytically determinable in terms of height of water column). The two values correspond to the 10 cm of water column (PF1) and 100 cm (pF2). The first value corresponds to the percentage by volume of water in the situation of “pot capacity”, after the draining caused by the gravity force.
The difference between the values corresponds to the percentage by volume of water available for the plants (easily available water + reserve water).
The concept is reflected in the curve of water retention.
The concept of hydrological class has been introduced by RHP fundation. Growing media characterized by different capacities for air belong to different hydrological classes.
How do you choose the most suitable soil?
From the agronomic point of view the criterion for an appropriate choice is:
Media with high capacity for air(low hydrolocical classes), are indicated for:
Growing in large container (> 16 cm), for the cultivation of long-cycle plants, for ebb flow irrigation systems, for species susceptible to roots diseases; Instead, substrates characterized by lower air capacity, ie high hydrological classes, are more suitable for: growing in a container of small or medium size, medium or short-cycle crops, sprinklers irrigation systems or subsurface irrigation. Clarified these agronomic concepts, each farmer will base its choice analyzing his culture system (type of irrigation, container type, etc.).