THIRDREALITY Smart Soil Moisture Sensor,Zigbee hub Needed,Accurate Measure,Capacitive Probe,Moisture/Temperature Meter for Garden Planting,Compatible with Homey,Hubitat, SmartThings,Home Assistant

I recently had a problem with root rot in my indoor Tea Rose. I'd been looking for a zigbee soil monitor for a while and my discovery of this lined up with my holiday shopping, so it seemed like the time to give it a try.The Good:Connects immediately to SmartThings, and so will also work with most other smart home ecosystems.Measures both temperature and "humidity".Waterproof (safe for outdoor use).Includes a battery.The Bad:What the description doesn't tell you - this thing is HUGE. Way bigger than the illustrations let on.The default SmartThings driver does not include battery level, but the device does report it.The ThirdReality Temp/Humidity driver includes battery, but only reports temperature OR humidity on the icon (you have to open the device in the app to see both readings).The Ugly:Digital soil meters are still not very common. This means there's no standards for measuring soil moisture and no standards for when to water various plants based on that digital reading.Humidity readings are reported very infrequently and take a while to update when the moisture level changes or if the meter is removed and replaced.I've had this for a couple weeks now. Overall I like it and would recommend, but it's not going to immediately solve all of your over/under watering problems. Set your expectations.It's not clear in the description or documentation how this device measures humidity. However, the design of the sensor post suggests it's measuring soil conductivity, like most analog moisture meters. It's also not clear how the reading is calibrated. And of course there are no instructions regarding what moisture levels are appropriate for what plants (though this is understandable, since ThirdReality is a tech company not a gardening company). What all of this means is that you'll have to do some science: Water according to your normal schedule and monitor the readings from this device in order to "calibrate" yourself.Once you've gone through a few watering cycles and seen how this reads, you can set your automations or alerts accordingly.Removing and replacing the sensor will alter its readings! I tested removing and replacing the meter. The reading went from 36% before to 0% removed and 10% after. I dug down a couple inches to confirm that the soil is still damp down below. This is likely just due to poor soil contact with the sensor probe, which will improve with watering and soil settling. This means that once you've place it and started your "calibration", it should stay put; removing it will require you to "recalibrate".For a version 2, I think they could reduce the size quite a bit if they tried. A smaller sensor would be nice, and most of the size is to accommodate the battery. I'd also like to see a version that could be externally or solar powered to reduce battery waste. And updating the ThirdReality ST driver to display both temp and humidity in the device thumbnail would be nice. But most of all, including a chart of "ideal water levels" for some common plants would elevate this substantially, making it a lot more user friendly for beginners or those trying to compensate for a "black thumb" (including this in a custom driver would be AMAZING).Still, after all that, tl;dr: It's worth the $20 and if you're reading this review then you should get it. But let's also hope they come out with an upgrade.I will probably buy several more of these and I'm considering the watering kit too.

The good:1. As others have mentioned, these things are big. That's excellent if you have bigger plants and want to be testing deeper.2. The design is solid and more durable than the only other option I tested, which is a tuya at a similar price point. These are, in every way, superior to those.3. Takes a standard, easy to replace battery. I'm sure I won't get as long when I replace them with rechargeables, but the alkaline that comes with looks like it should run 6-12 months.4. Paired easily with Home Assistant. Polling frequency is more often than it needs to be, but doesn't seem to be a problem.Now the bad: You can see by my screenshot, three of the same devices placed within inches within the same pot, one was wildly off, the other two I was expecting to be closer in terms of measurement. Stated accuracy is +/-5 and soil moisture can vary, so I'll give the benefit of the doubt and say two of the three were within tolerance. That's not terrific.Bottom line is that if they at least over time show consistency within each unit I can calibrate and work with it. Would be nice for a more precise sensor.UPDATE: Company got in touch with assistance, very happy with their approach. Upgraded from 3 to 4 stars.

I have used these for about a month now - they are quite reliable and provide good perspective on soil hydration. My temp sensor is pretty much right on with the other temp sensors in the reasonable range in our house. I keep the house around 70 and this thing seems to agree with the thermostat. If it were not accurate, it would be easy to fix - all thermos need calibrated from time to time and its fairly normal for one sensor to not match another. Pick the easiest to calibrate accurate - calibrate that one - then adjust the offset on everything else to match it. Quite easy to do this in Z2M - see the settings in photo attached.As far as the humidity in the soil - thats kind of a known problem as far as measurement goes. There isn't really a great way to test how much water is in soil... especially if you are attempting to do it with constant reporting over the course of a year with a AAA battery or two. The accuracy isn't the value here though. The value is in the trend reporting. I legit couldnt care less what the actual number is (or, more accurately, what its correlation to "true" is) - what I can do, however, is notice that after this sensor reports below 35 ( or whatever ) the leaves on my plant start drooping. That is the calibration - that is the accuracy. And this device is perfect in that scenario - I can see the trends and know what to do from there... No device at this price point or this level of energy efficiency will be able to do more than that - there are simply too many variables (everyone's rain and soil is different!). After observing trends for a while, you will realize the actual number doesn't matter. If it does matter, put it in the driest soil you can find and offset that to 0!As far as connectivity goes - I have had no issues. I have a robust zigbee network and it has a multitude of lightbulbs and other mains powered zigbee devices from which to join the mesh in its vicinity. A quick glance at my Z2M map shows it comically connected to one of the furthest possible bulbs at the moment and the connection quality is still fine.My only complaint on these (have a couple more on the way actually) is that shipping from Amazon is so slow but I am chalking that up to being a newer product.