It depends on several factors, including how well you care for the tree and the quality of the tree itself. On average, a cut tree can last anywhere from 2 to 6 weeks, with some varieties lasting even longer. Properly watering the tree and keeping it away from heat sources like fireplaces or heaters can help to extend its life. Additionally, some people choose to use tree preservatives, which can help to prolong the life of the tree by providing essential nutrients.