Merced County, CA Landscaping Rules: Native Plants (2026)

Far from restricting native plants, Merced County's Unified Development Ordinance encourages them. Under UDO Section 18.36.050(A), the selection of plant materials must include 90 percent drought-resistant and well-suited to the local climate or naturally occurring species, with no more than 10 percent non-drought-tolerant material - and even that 10 percent should be grouped together for possible separate irrigation. Plans must combine deciduous and evergreen trees, shrubs and groundcover and use plants that help prevent dust, erosion, heat and glare. Section 18.36.050(B) caps turf at 30 percent of the total landscaped area (Director may grant exceptions) and sets minimum sizes (shrubs one gallon, trees fifteen gallons), while allowing groundcover such as rocks, gravel or wood mulch/chips between plants as they mature. For street trees, Section 18.36.050(H) directs the use of indigenous and drought-tolerant species to promote water conservation, with one drought-resistant species per subdivision and a preference for trees that won't damage foundations or sidewalks. These County standards work alongside the state MWELO (adopted in Section 18.36.030), which similarly rewards low-water, climate-appropriate plantings. There is no Merced County rule banning native or pollinator gardens; a tidy, intentional native landscape is consistent with the code - just remember dry, ignitable growth still must meet fire-abatement standards under Chapter 9.25.