9 county-level rules, plus city-specific rules for 11 cities in Honolulu County, Hawaii.
Verified from official government sources
Honolulu County regulates overgrown vegetation as a public nuisance under ROH Chapter 16A rather than setting a fixed grass height, applied island-wide across Oahu by the Department of Planning and Permitting.
Honolulu County requires permits from the Department of Parks and Recreation Division of Urban Forestry for planting, trimming, pruning, spraying, or removing trees in the public right-of-way across Oahu under ROH Section 10-1.4.
Honolulu County protects designated exceptional trees island-wide under ROH Chapter 40, Article 8, prohibiting removal or destruction without a Parks and Recreation permit except in emergencies under Sec. 40-8.9.
Honolulu County regulates weeds on vacant lots island-wide under ROH Chapter 16A, Section 16A-2.1 et seq., with a 30-day owner-notice process before the county may enter and abate at the owner's expense.
Honolulu County authorizes water conservation under ROH Chapter 30, Section 30-2.3, while day-of-week irrigation and stage-based shortage rules are issued by the Honolulu Board of Water Supply separately for the entire island.
Honolulu County has no ordinance restricting residential rainwater harvesting; the Board of Water Supply encourages it countywide through a rain barrel rebate program and CTAHR catchment guidelines.
Honolulu County permits native Hawaiian species as landscape substitutions under LUO Sec. 21-4.70 but does not mandate native-only planting; voluntary guidance comes from the Board of Water Supply Xeriscape Program.
Honolulu County has no specific ordinance on artificial turf; LUO Sec. 21-4.70 governs landscape area requirements countywide, and Planning and Permitting decides case-by-case whether synthetic turf satisfies landscape percentages.
Honolulu County mandates food waste recycling under ROH Sec. 42-3.5, with Ordinance 23-30 adding curbside food scrap collection island-wide by April 1, 2025 through the G.R.O.W. Program.
11 cities in Honolulu County have their own landscaping rules rules. Each link goes to that city's dedicated page with code citations.
5 verified rules • Grass Height Limits, Tree Removal & Heritage Trees
9 verified rules • Artificial Turf, Composting
9 verified rules • Artificial Turf, Composting
9 verified rules • Artificial Turf, Composting
9 verified rules • Artificial Turf, Composting
9 verified rules • Artificial Turf, Composting
9 verified rules • Artificial Turf, Composting
9 verified rules • Artificial Turf, Composting
9 verified rules • Artificial Turf, Composting
9 verified rules • Artificial Turf, Composting
9 verified rules • Artificial Turf, Composting
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