Temperature Trials - Hosted By Spruced Nursery We tested temperature over time during Summer using Elitech temperature loggers inserted in the growing media of nursery pots under PotHeads. This data was compared to open (control) pots tested simultaneously. No signficant difference was detected over 9 days of trial data collection. It was observed that pots were slightly insulated by the PotHeadsᵀᴹ overnight reducing average minimum temperatures slightly. Even with black PotHeadsᵀᴹ, maximum midday temperatures were on average just 1 degree Celsius higher.