Arlington Heights, IL Landscaping Rules: Weed Ordinances (2026)

Arlington Heights property maintenance ordinance requires all properties to be kept free of excessive weeds and overgrown vegetation. Weeds, like grass, must not exceed 8 inches in height. Illinois law designates certain species as noxious weeds that must be controlled regardless of height, including Canada thistle, perennial sowthistle, and other species listed in the Illinois Noxious Weed Law (505 ILCS 100/). Property owners must control weeds on all portions of their lot including parkway strips and areas adjacent to alleys. Vacant lots are subject to the same weed control requirements as occupied properties. The Village issues notices of violation when weeds exceed the height limit or when noxious weeds are present. Property owners typically receive 5-7 days to bring the property into compliance. If the owner fails to act, the Village may hire a contractor to mow and clear weeds, and the cost is billed to the property owner or placed as a lien on the property. Managed natural landscapes with native plantings are distinguishable from weed violations when they are clearly maintained with defined borders and intentional planting patterns.