Artemisia Geyser is part of the Cascade Group which includes the Atomizer Geyser. It erupts for a duration of 15 to 25 minutes once or twice per day. The fountain reaches a height of 30 feet (9.1 m). Artemisia's pool overflows quietly for many hours before an eruption, but gives no visible warning of an impending eruption until the sudden increase in overflow that marks the eruption's onset. Eruptions are accompanied by a strong underground thumping caused by steam bubbles collapsing in the geyser's channels.
Artemisia also experiences minor eruptions lasting about 5 minutes. These minor eruptions are followed by major eruptions within six hours. Minor eruptions are rare. Years may pass between episodes of minor eruptions.
In 2009, intervals between eruptions ranged from 9 to 36 hours, averaging 18 hours, 43 minutes.