Descaling irrigation water - does that have to be?

Again and again, it is strongly advised to descale the irrigation water for plants. Why this must be supposed to have consequences for lime-containing water for plants, and with what methods one can and should descale is therefore discussed in detail here.

Plants and water hardness

Plants are usually supplied with rain in the open air. Rainwater is practically distilled water.

It has a pH of between 5.5 and 6.5, depending on the amount of carbon dioxide that is dissolved in it. The rain absorbs carbon dioxide from the atmosphere when it is on its way to Earth. Rain does not contain any minerals. So all hardeners are missing.

However, most plants tolerate tap water easily. Only very sensitive plants, such as some orchid species, may occasionally have problems with individual minerals. This is a rare exception.

Up to a water hardness of around 20° dH, one can assume that most plants have no problem with it. But you should be careful about that, so that no lime layer accumulates in the plant and on the substrate. It can complicate the nutrient uptake of the plants.

Plants need minerals

Minerals are vital for plants, as for most organisms. The minerals, which contain tap water, accumulate in the substrate as they are poured, and can also be used as nutrients by plants. This deficiency symptoms are avoided in many cases, which otherwise have to be compensated by fertilizer, if the respective nutrient does not occur in the substrate.

Soften water for plants

The easiest way to soften the irrigation water is to dilute it with distilled water. With a mixture of 1/3 distilled water to 2/3 tap water, the calcium content of the tap water is already significantly reduced.

Tips & Tricks

Under no circumstances should you use water for pouring, which comes from a water softening system. Ion exchangers enrich water with a high amount of sodium. This salted-up water can be deadly to many plants!

Video Board: Why Salt Water Softeners Are Dying