St. Charles County, MO Landscaping Rules: Weed Ordinances (2026)
Key Facts
- Height limit
- 10 inches
- Applies to
- developed lots + adjoining right-of-way
- Noxious weeds
- prohibited at any height
- Governing code
- Property Maintenance Code § 302.4
- Waiver
- code official may waive if safe
Summary
St. Charles County caps weeds and grass on developed lots at 10 inches, with noxious weeds banned outright regardless of height.
All developed premises or exterior property shall be maintained free from weeds or plant growth in excess of ten (10) inches. For purposes of this provision, premises or exterior property are "developed" if improved with any structure or if used for outdoor storage of materials or if within a platted subdivision. ... All noxious weeds shall be prohibited. Weeds shall be defined as all grasses, annual plants and vegetation, but not trees or shrubs, or agricultural crops, or gardens in the rear yard, or cultivated flowers.
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: rev 4863880; v61 updated 2026-05-11; through 05-11-2026).
Full Breakdown
Under the county's Property Maintenance Code, every developed lot, anything with a structure, outdoor storage, or inside a platted subdivision, must stay free of weeds and plant growth over 10 inches. The duty extends past the property line to any adjoining public or private right-of-way, so owners maintain the grass up to the curb or pavement edge. Noxious weeds on the Missouri Department of Agriculture's list are prohibited outright, no height threshold needed. The code official can waive the 10-inch limit case by case, but only where doing so won't create a health or safety risk.
Violations & Fines
Code Enforcement issues a notice of violation; failing to correct it triggers prosecution under Section 109.3 and the county may abate (cut) the growth itself under Section 500.510 and bill the owner.
Frequently Asked Questions
Does the 10-inch limit apply to my whole yard?
Are wildflower gardens or crops exempt?
What happens if I ignore a violation notice?
Sources & Official References
Other rules in St. Charles County
How St. Charles County compares: Cities with the Strictest Weed and Property Maintenance Rules·Compare St. Charles County to another location·View the Missouri landscaping rules overview
See something wrong?
Help us keep this page accurate. If you notice an error or outdated information, let us know.