Whilst small amounts of softened water may be safe for some types of plants, it’s generally not recommended for your plants—especially in the long term. Water filtration experts recommend avoiding using softened water when possible and opt for rainwater or purified water (that has been through a water filter) instead. If you have a water softener installed at home, there are still ways that you can safely water your plants, as we will explore in this article.
What Is Softened Water?
Softened water is water that has been treated to remove the calcium and magnesium from a hard water supply, in order to prevent the build-up of limescale in a property’s plumbing system and home appliances.
The most common process used by water softeners to trap and remove hard water minerals is called ion exchange, whereby sodium ions replace calcium and magnesium ions.
What Is the Point of Softening Water?
There are many benefits of using softened water in your home. First and foremost, soft water does not cause limescale as hard water does, and actually gets rid of any existing scale deposits in your pipes that were caused by hard water. This means your plumbing system can run more efficiently; reducing your household bills and saving on energy, which makes your home more environmentally friendly.
Softened water is also kinder to your skin and hair, which is advantageous for those with sensitive skin. It can even improve conditions such as eczema, dermatitis, or psoriasis.
Many people prefer the taste of soft water, although this depends on personal preference and what you are used to.
Why Is Softened Water Bad for My Plants?
We may enjoy the pleasant effects of softened water in the home, but it’s a different story when it comes to your plants—no matter if they are potted and indoors, or living outdoors in your garden. The high concentration of sodium in softened water (compared to other water types) upsets the balance of water in the plants and herbs themselves, as well as in the soil.
The excess sodium in the water tricks your plants into a state where they think they have absorbed more water than they actually have, which results in thirsty plants. Used often enough, softened water will not only damage your plants but can completely kill them.
And, there’s even more potential for long-lasting damage when it comes to your soil. If sodium levels build up in the soil (or other growing materials), it can prevent healthy plant growth in the future.
What Water Should I Use for My Plants?
Reverse Osmosis Water Filter
Given that soft water is unsuitable for the job, what water should you be using? One of the best options is water that is treated by reverse osmosis (also known as RO) which produces clean, freshwater—greatly reducing any contaminants (molecules and ions) like microorganisms and bacteria. Such impurities can cause many unwanted issues such as fungal diseases or root rot.
Many gardeners choose to use RO treated water because it allows greater control over the nutrients that they give to their plants, by adding fertilizers or plant food to the clean and pure water.
Many water softeners have a bypass valve that allows you to direct water away from the system, and in some cases, it is even possible to collect the water in its ‘original’ state from an outdoor tap.
How to reverse the damage caused by watering plants with softened water
If you’ve been feeding your plants with softened water, do not panic! It is possible to remedy the damage by a process called leaching. This basically means frequently watering with purified or rainwater in order to flush out and drain the salt from the soil.
Given enough time, your plants should recuperate and you will see a full recovery.