The influence of expanded clay on the pH value of irrigation water and substrate is a hotly debated topic among gardeners. With this article we try to shed some light into the darkness. We explain how expanded clay can affect the pH value.
How does expanded clay affect the pH value?
Expanded clay produced under the best conditions is consideredpH-neutral, so it does not change the pH value in the substrate or water. However, clay balls of poor quality or not properly sealed ensure that thepH value increases
Is expanded clay pH neutral?
In theory, expanded clay is biologically and chemically neutral and therefore also pH-neutral. In practice, however, things often look different. If the clay is not heated at 1200 degrees, but at lower temperatures for cost reasons, the surface of the balls is not reliably sealed, so substances can enter and exit, which logically destroys the pH neutrality.
How much can expanded clay increase the pH value of the water?
According to the experiments of several independent hobby gardeners, the pH value of water with expanded clay increases on averageby 2.5. Example: If the irrigation water initially has a pH value of 5, after a few hours with the clay balls it will be around 7.5.
Note: How much expanded clay actually increases the pH value always depends on the product in question. The manufacturer usually provides information about the approximate pH value of the clay beads on the packaging.
How can I keep the pH value stable despite the expanded clay?
With suitablepH value reducersyou can keep the pH value of the water and substrate stable even if you want to use expanded clay - whether as drainage or in hydroponics. It is important tomeasure the pH value regularly for all measures.
Note: It is always recommended to wash the clay balls thoroughly before using them for the first time. In principle, this makes sense to free them from the dust that often surrounds them. However, it is doubtful that this measure really makes the balls more pH-neutral.
Tip
Only use high-quality expanded clay
Always only use high-quality expanded clay. Then there is a good chance that the beads have little or no influence on the pH value of the substrate and water. So it's better to invest a little more money in order to get the highest quality expanded clay for drainage or hydroponics. In this way you are doing your plants a favor and saving yourself time and stress later.
