Best practice for bringing plants indoors for the winter in Philadelphia?
Depending on the plant, the ideal temperature for wintering over plants is 50 degrees with moderate humidity, low but consistent light and water as needed (not totally dry and not overly wet). An unheated room with north facing windows would work or a sunroom with windows you can open to release excess heat. Remove any bugs you see and if the plants are potbound repot them in larger containers. Different plants will require more or less exposure to sunlight so look up requirements for your individual plants.