It works!

Ok, so the first thing that needs to be said is DON'T PUT IT IN WATER. It even says it right there on the package and the listing and pretty much everywhere, so that's not a metric at all of if it's accurate.

From what I can tell from a few days use it is accurate. Using it on 'green zone' regular hardy plants that require normal watering showed at dry (though it didn't look super dry, but the sensor is reading internal and we are seeing surface soil), but when I watered it and waited a bit, it immediately went up to the green 'correct' zone. So to me, it seems as though it works. I will say that it takes very little water to increase the zone, so be careful not to overwater your plants and continue to check every day until you get a 'feel' for what each plant needs. Cacti are in the dry zone, as they should be.

It isn't the most extravagant professional feeling sensor. It's chunky plastic with a metal spike, but thus seems more sturdy and let's be frank, it's only 10 bucks (at time of review), so I wasn't expecting $50 quantity. Considering the cost and functionality, I'm perfectly happy with it.

The only flaw I could say is that having the 'list' of plants on the box means most people will toss it. I recommend taking a picture with your phone so you always have it and it might be cool if they had a list or database online somewhere, but over time you'll learn which plants need what. It's clear, easy to read and works, for bargain hunters, this works just fine!