Soil moisture or pH test probes

Perhaps check your metres against something you know to be reasonably correct.

If you have such a device that you can test the moisture or the pH of the soil or MM you might have to do what I had to do this afternoon.

I hadn't used them since early March and they developed a dark tarnish on the copper probe.

This tarnish is an insulator , gives a high circuit resistance and thus affects the readings of the meter tremendously .

Simple use some soft wire wool or some very very fine wet & dry or some slightly abrasive stainless steel sink cleaner to clean the tarnish off so you get clean bright copper .


Doing this took what I knew to be sopping wet plants giving a reading of dry to what it should be at very wet ( I'd just watered them )