HI Melissa-
Your question is answered in another thread "Rainproof?"
http://easybloom.com/sfSimpleForum/topic/id/86/stripped_title/rainproof
Here's what Robby said before "The EasyBloom Plant Sensor can definitely be left out in the rain. As long as the sensor is not left out in torrential downpour or thrown in a puddle or pool, it will be fine. The sensor is water resistant, but I would not say that it is waterproof or rainproof. I have let the sensor outside when it rained overnight. The next day I uploaded the data. It was cool to see the data graphs show the soil moisture and relative humidity shoot up. I hope this is helpful. --Robby"