Don't buy this, it is a piece of **** !
Huge, ugly, spammy, and extremely badly written firmware. It just stops reporting the temperature and the humidity after some time, or the humidity locks on 100%.
The best affordable plant sensors that I have are the Aqara/Xiaomi sensors :
I had these Buletooth devices connected to Home Assistant and then linked to Hubitat via the community HA->HE bridge. And they were working very well, but at one point I stopped using them and never had the time to put them back in operation.
You can always go around and check your plants, checking that they are not lacking in water and other nutrients.... Can't say I follow this advice, but I assume it is part of the appeal many have for getting into gardening.
Rainbird makes a sensor that basically has cardboard like disks inside of it that are used to detect water. You can adjust it by turning the top to the amount of rain you desire to shut off the irrigation controller. This sensor works with most irrigation controllers including Rachio. I have the Tempest integration with my Rachio but still use this sensor as well.
Yeah that drives me nuts given a rain sensor is only $20 and super easy to install.
That matches my experience using the WH31SM in my lawn. We just went through a stretch of rain here (about 2" over a 48 hour period). Last night the sensor got as high as 88% during the showers; this morning it's down to 59% already (sun is out but there is standing water still in the street and temps are still mid 50's).
I started using one of mine in a large indoor planter that has a (supposedly) indestructible plant that we have a tendency to overwater (sanseveria).
I recently replaced a dead one with a new plant and the soil that came with it; I transferred the sensor at the same time with the new planting (it had settled to 5% since watering had stopped when the previous plant died). When inserted with the replacement plant, the sensor fairly quickly rose to around 14% (the soil didn't feel particularly dry; in fact it was dark and would clump together if you pressed it but wasn't noticeably wet).
The sensor's readings very gradually rose to 18% over a period of several days and have remained at that level for about a week now. Since the plant supposedly doesn't like wet conditions I need to find an appropriate 'low nominal' to trigger a water reminder (I'm assuming the plant as delivered was OK with 18% moisture level though not sure what dryness level would trigger a knowledgeable gardener to add water).
Can't say I follow this advice, but I assume it is part of the appeal many have for getting into gardening.
