The new ordinance was written in response to at least six businesses in the past year that have cut down trees that block business signs.
"Many businesses have abused their landscape requirements," Commissioner Phillip Walker said after the meeting.
Cutting down trees for sign visibility has increased recently, said city horticulturist and landscape inspector Bill Koen.
Bruce Kistler, planning manager for the city, said the previous city code had only implied that businesses must maintain landscaping.
If a tree is taken down for sign visibility, Kistler said, the businessperson may be fined or required to install additional landscaping on the property.
The commission voted 6-0 to add the fines, with one absence.