Boulder, CO Landscaping Rules: Composting (2026)

Section 6-3-6(a) of the Boulder Revised Code affirmatively permits any person to maintain compost piles, but requires the pile to sit in a segregated area and to contain alternate layers of plant material maintained so it decomposes into organic material usable as a soil conditioner. Subsection (b) then places the burden on whoever maintains the pile to prevent it from becoming a nuisance, specifically from putrid odors or from attracting wildlife or pests such as rodents or insects. A compost pile kept in conformance with Section 6-3-6 doubles as a legal shield elsewhere in the chapter: Section 6-3-7(c) makes compliance with Section 6-3-6 an affirmative defense to a charge of improperly storing trash, recyclables, or compostables under Section 6-3-5(a)(1) and (2), and Section 6-3-17(b)(6) exempts a property or business owner who composts on-site in compliance with Section 6-3-6 from certain recyclables-and-compostables collection obligations elsewhere in the chapter.

Because compost piles are exempt from the general storage rules in Section 6-3-5 as long as they meet Section 6-3-6's segregation and layering standard, a resident does not need a bear-resistant enclosure or screened container for an in-conformance pile the way they would for stored trash or recyclables.