Conclusion:

If you bring this sensor into your home, you make your plants a lot smarter. You can check whether they have enough water, not too much/too little light, whether he has enough food and whether it is not too hot (or too cold).

Very useful information to see if your plant is healthy. And of course also to make sure you don't forget to water it.

This sensor uses the BT protocol, so you do not need a controller to read the values. A disadvantage after this is that the range is somewhat limited (maximum 10 meters).

You can buy the MI Flora sensor for around 18 euros. If you need 2 then these costs are manageable, but you would actually want to have it in all your plants and then it can of course run into the paper.