Gymnosperms are preferred for the purpose of outdoor decoration because most of them are evergreen.
What are evergreen plants?
The evergreen are those plants that remain green throughout the year. They are very useful for the purpose of decoration because of the nice green leaves they have all year round.
Now, most gymnosperms are evergreen plants hence gymnosperms are more palatable for use in decoration.
Learn more about gymnosperms: https://brainly.com/question/4526473
