Ninety days of GrowSpot Plus. Reads light, temperature, humidity and airflow at one exact spot and tells you what will actually live there. How it works: redeem the code in Google Play (Play Store > your profile > Payments & subscriptions > Redeem code, or paste it at play.google.com/redeem), then open GrowSpot and tap Subscribe. The 90 free days apply at checkout. After 90 days it renews at the normal price unless you cancel, and you can cancel any time in Google Play.