It's probably better than nothing at all but if you don't have any information on it other than "it's for houseplants" we can't tell you how effective it's going to be! If you use is on cloudy days, I would get it as close to your grow as possible (6"?) but monitor the top leaves to make sure they're not getting burned... at the SLIGHTEST hint of trouble, move it away a bit and continue monitoring... you should be able to figure out the sweet spot and use it accordingly... Nice neighbor, btw! Good luck!