Water for orchids: hardness and pH

As an additional piece to a previous post about water for orchids, I wanted to share my recent findings with testing my tap water for hardness and pH.

A sample of our tap water to be tested for hardness and pH.

I’ve recently moved home and I suspect that the tap water in our new house is harder than our previous home. The water test kit I purchased from a local aquatics centre has baffled me so much I have acquired some electronic meters to test the water hardness and pH. These meters are available on Amazon or eBay for a reasonable price – I think I paid £12 for both.

Given that they are not the flashiest equipment available, I’m expecting some degree of inaccuracy, but for now I only want a rough idea of what the water is like. Drumroll please…

pH meter reading – a little too high.

TDS (total dissolved solids) meter reading – too high for my liking!

What does this tell us?

As I mentioned in my previous post, Water for Orchids, tap water is perfectly fine for orchids, so long as the water is soft and the pH is neutral. However, the tap water in my new home appears to be harder than my orchids are used to, which poses a few issues. Reading at 186ppm (parts per million) the tap water can be classed as fairly hard water. The pH is slightly too high as well which may also present a few issues.

So what are my options?

I can either look for a water softener, or I could look at rain water, distilled water or reverse osmosis water in more detail. Each will have its positives and negatives, but I am happy to experiment. How else will I learn what works best?

My first plan is to collect rain water (let’s face it, it’s pretty abundant in the UK!), and check it for suitability. A number of orchid growers prefer to use rain water for orchids given that it is low in dissolved solids and the pH is balanced. There is little pollution where we live, so it should be fairly free of additional chemicals.

I’ll continue to use the tap water for the time being, but adjust the fertiliser quantity accordingly so the orchids are not receiving high doses of anything.

I will just point out that you do not have to follow my example or advice and change your water type to accommodate your orchids, if you do not feel the need to. If your water is classed as hard water however, I would advise keeping an eye on water deposits in the media you grow your orchids in. If there is a build up within the pot, it can cause poor absorption to the roots and thereby create issues for your orchid.

If you have any questions, please feel free to leave me a comment, and I’ll get back to you.

Happy growing!

Clare