Hard water irrigation

What are hard waters?

Hard waters are those that present in their chemical structure a high concentration of minerals, such as bicarbonates, but mainly calcium and magnesium salts. The combination of the latter is known as CAL. Because of this, hard waters are also called calcareous waters.

Hard water characteristics 

• It contains a high level of minerals, usually calcium and magnesium salts, but it can also contain carbonates, chlorine, fluorine, iron and zinc.
• It is usually water of underground origin, in calcareous soils.
• It is not suitable for domestic or industrial use.
• To calculate the hardness of the water, the concentrations of calcium and magnesium contained in one liter of water must be added.
• It can be present permanently, since it can contain sulphates and chlorides in its structure and / or temporarily, since it contains carbonates in its composition.

Hard water irrigation

In some cases, irrigation with hard water is beneficial for certain plants, since in this way they receive a load of minerals that can be beneficial for their development, including aluminum, iron, nitrogen, zinc, etc.

Acidophilic plants, hydrangeas and camellias among them, are affected by the use of hard water for irrigation, since the pH of the soil is altered.

In cases of sodium soils, the use of hard water is recommended as a measure to compensate for the negativity of the sodium cation in the soils (Na⁺). In the case of very compacted soils, therefore hard soils, irrigation with this type of water is not the most indicated, as the permeability of the soil is further affected.

When water contains a considerable amount of dissolved calcium, magnesium and carbonates, it is called hard water. Calcium and magnesium are essential nutrient substances for the development of our plants. However, an excess or imbalance of these nutrients can cause alterations. Commercial fertilizers contain a certain amount of calcium and magnesium depending on the water to be used.

It is necessary to know the quality of the water when phytosanitary treatments are to be carried out on crops, since its efficiency will depend on the concentration of minerals it contains. For this, a laboratory is required to carry out the specific tests of the case.

How to soften tap water to water plants

In general, in apartments, and many times at home, the water we use for our plants comes from the tap, and we know that it is a type of hard water, as it has been treated with some chemical elements to make it suitable for human use. .

But we can make it less hard, or soften it to be able to use it in watering our plants. There are a few tricks we can use to avoid hard water damage, including:

• If it is only the indoor plants that you are going to water, collect the amount of water you usually use in a container, let it rest for a day, and put 2 - 3 drops of vinegar for each liter of water collected. You can do the same with drops of some citrus in the collected water (lemon, lime, orange). This can be done once a month. In this way, the acidity that the substrate has lost will be restored.
• Collect the water in a container and put hardness reducing products or softening products, which you will find in garden stores. You let it sit for 6 hours, and then you filter it with a canvas or fabric strainer.
• In garden stores you can get special watering cans, with filters to use tap water. By means of this filter, the concentration of lime and additives contained in tap water is reduced.
• Peat also absorbs lime from the water. To achieve this, prepare a bag that can be closed, or a bag that you must seal very well, with 500 gr. of dry peat. Collect the water in a container, place the bag with the peat on top of the water, holding it with a stick. In this way the peat absorbs the lime, being able to use it up to three times. You can buy it in garden stores.
• The simplest way is to collect the water in a container, leave them in the sun for 24 hours, and then you can water your plants.

Disadvantages of hard water irrigation

Lime can get trapped in the roots of the plants and form solid structures there (incrustations) that will prevent the absorption of other nutrients that are added to the fertilizers.

The continuous use of this type of water will generate that the salts contained in the water accumulate in the substrate of the plant. This excess salt can cause the roots to burn, in addition to preventing them from absorbing moisture properly. To make matters worse, hard water is also the culprit in forming a white layer on the surface of the soil in the pots, giving them a bad appearance.

In irrigation systems, obstructions or clogging usually occur due to the fact that lime precipitates in the emitters, thus preventing their correct exit of water. The irrigation systems that are most affected are drip irrigation systems.

In very hard and compact soils, the use of this type of water is not recommended, because it does not improve the permeability of said soil.

In some cases, hard water will interfere with the stability of certain substances that are used in phytosanitary treatments, altering or modifying the purpose of said treatments.

A substrate with excess minerals can become alkaline due to constant irrigation with hard water. Plants will suffer and show slow or no growth, their leaves will appear yellow with dry edges or may also turn brown. If the situation does not improve, the leaves will appear wilted and may even begin to fall. This will show that the roots have been burned from excess lime.

How to solve problems that cause hard water in the irrigation system

To avoid the problems caused by limescale deposits in irrigation systems, the most effective solution would be through the use of equipment known as a descaler. It is a very expensive device for an irrigation installation but, in the case of a house with a garden, it would be worth thinking about it, since it also improves the water for domestic use.

Hard water will cause obstructions in drip irrigation systems, as well as in solenoid valves. For this reason, it is recommended, in the case of solenoid valves, that they be piloted hydraulic.

The most commonly used technique to remove lime from irrigation systems is to soak or submerge the emitters in a soft liquid. This is in order to achieve the dissolution of the precipitates that are in them. This method could be named as the home method, because the "mild" acid used is vinegar, since it is easier to dispose of this type of acid, although its effectiveness is shorter.

It is convenient to install drain valves in drip systems, as this reduces the risk of hard water remaining in the pipes.

Unusually, acid is injected into the pipe in order to "dissolve" the precipitations or incrustations found there. This method is known as the agricultural method. Likewise, by way of prevention, it is possible to resort to the placement of an acid injection system in the installation.

If you want to know more and need extra information, do not hesitate to visit our website and contact contact with us, and we are also experts in dosing pump, Bilge Pump, fertilizer and in drip irrigation accessories.