With cooler temperatures on the horizon, many people will be cranking up the heat. However, there is one secret that gardening experts know and that is houseplants cannot thrive next to a heater. Most houseplants do well in homes with temperatures ranging from 65 to 75 degrees Fahrenheit. Tropical plants can withstand even higher temperatures — up to 85 degrees – which could lead you to falsely believe that keeping these plants near a heater would be fine. While temperature ranges can vary depending on the unit, many central heaters start by pushing out air that is between 140 to 170 degrees Fahrenheit.