There are a few items in Pokémon Go that can be used to help players customize their experience in the game, including the Incense.
This item will passively attract Pokémon directly to a player for a full hour, usually averaging one encounter per minute while active.
But as Niantic continues to develop Pokémon Go and add more content, there has also been a slight update to Incense. It doesn’t change the core mechanic of the item, but it does ensure there is a more situational version that can be utilized for events and special offerings.
The base version of Incense has a green and white color scheme and will attract any and all Pokémon that are available to capture in the wild. The only limit placed on it is the one -Pokémon-per-minute spawn rate so players aren’t being overwhelmed and won’t abuse the item.
More recently, an orange variant of Incense has been rolled out during Community Day and other special events, which will only attract specific types of Pokémon.
Most notably, during Incense Day, which is a more recent addition to the recurring event lineup for Pokémon Go, it will only spawn specific types of Pokémon depending on the time of day. The first event rotated between Dark and Water-type Pokémon every hour, so an Incense would swap between the two at specified times.
Outside of that one mechanical difference, there is no other major difference between the two Incense colors. Just know that you likely won’t be seeing orange Incense outside of specific events or periods where Niantic is pushing one type of Pokémon.