A dogwood tree can have a relatively long life with the correct setting and ongoing care. In ideal situations, these trees can live to be 80 years old or more. During that long lifespan, this tree will maintain a manageable size. The best way to help your dogwood enjoy a long life is to meet the specific requirements it needs to thrive. Acidic soils, partial sunlight, and consistent moisture are among the factors that influence this plant's longevity.