St. Peters, MO Landscaping Rules: Weed Ordinances (2026)

Section 215.010(H)(1)(a) bars grass or weeds over seven inches on any lot or tract that includes a building under construction, or on common ground, in a residentially zoned district, and on lots elsewhere used for residential purposes. Subsection (c) extends that same seven-inch cap to all multiple-family developments once the first occupancy permit issues. Subsection (d) applies the identical seven-inch ceiling to commercially, industrially or institutionally zoned lots or tracts that already include a building or a building under construction, making the improved-lot limit uniform across residential and non-residential districts alike once a structure exists.

The banned growth is described broadly: jimson, burdock, ragweed, thistle, cocklebur, milkweed, buckthorn, dandelion, henbit, crabgrass, goosegrass, foxtail, nutsedge, poison ivy, and any other rank vegetable growth that produces unpleasant odors or conceals filthy deposits, plus grass of any type. Growing brome, alfalfa, timothy or clover for hay purposes is separately banned in residential districts regardless of height. The City reserves enforcement authority under Section 215.010(H)(1)(h) whenever vegetation growth creates a health or safety problem, including harboring rats, mosquitoes or vermin, or a fire hazard, independent of the height trigger.

A property that violates the limit more than once in the same growing season loses its right to further notice: under Section 215.010(H)(1)(f) the Chief of Police or another designated official may order the grass cut and bill the owner directly. Violations of Chapter 215 carry the City's general penalty in Section 100.060, up to a five hundred dollar fine, ninety days imprisonment, or both, with continuing violations counted day by day.