Honolulu's Landscaping Rules: The Rules That Matter

Every city handles landscaping rules a little differently. In Honolulu, Hawaii, there are 5 distinct rules that residents and property owners should be aware of. Some are stricter than what neighboring cities enforce, and others are more relaxed. Here is what you need to know.

Grass Height Limits

Honolulu requires property owners to keep their land free of excessive weeds, overgrown grass, and waste. Uncultivated flammable weeds exceeding 18 inches within 30 feet of a building in residential or apartment zones are defined as a public nuisance.

Key details: Nuisance height threshold: 18 inches near buildings. Proximity rule: Within 30 feet of any building. Owner notice period: 30 calendar days to comply. Maximum daily fine: Up to $5,000 per day.

Civil fines up to $5,000 per day (raised from $1,000) for failure to maintain property after notice. City may abate and place a cost lien on the property.

Water Restrictions

Honolulu's Board of Water Supply (BWS) may declare mandatory water-conservation stages restricting outdoor irrigation timing and volume. The Land Use Ordinance also requires permanent irrigation systems for required landscaping on development sites.

Key details: Conservation authority: Board of Water Supply (BWS). Irrigation system required: Yes, for LUO-required landscaping. Restriction levels: Voluntary to mandatory stages. Violation penalty: Misdemeanor, daily fines.

Violations of BWS mandatory water restrictions are a misdemeanor under ROH Chapter 1, § 1-3.1; fines escalate and each day of continuation is a separate offense. Service termination is also possible.

Weed Ordinances

Honolulu's ROH Chapter 41, Article 10 requires property owners to cut and remove weeds and waste that constitute a public nuisance. Owners have 30 days to comply before the city abates at owner's expense.

Key details: Compliance notice period: 30 days. Maximum daily fine: $5,000 per day. Cost recovery method: Lien on property. Governing chapter: ROH Ch. 41, Art. 10. Enforcing agency: Building Dept. / DPP.

Fines up to $5,000 per day for failure to maintain. City may abate and place a lien on the property for all costs. Enforced by the Building Department and DPP.

Tree Trimming

Honolulu requires permits for trimming, pruning, or removing street trees in the public right-of-way (ROH § 10-1.4) and for any work on city-designated exceptional trees under ROH Ch. 40, Art. 8. Fines up to $1,000 apply for violations.

Key details: Street tree permit: Required – apply via DPR. Exceptional tree permit: DPR + qualified arborist required. Max fine: Up to $1,000. Removal authority: City Council approval needed.

Unpermitted trimming or removal of street or exceptional trees: fines up to $1,000 per violation. Exceptional tree removal without City Council approval may require restoration.

Tree Removal & Heritage Trees

Honolulu protects designated 'exceptional trees' under Revised Ordinances of Honolulu (ROH) Chapter 40, Article 8. Removing or destroying any exceptional tree without City Council approval is unlawful (ROH § 40-8.8). Any pruning of branches or alteration of an exceptional tree's characteristic shape requires a permit from the Department of Parks and Recreation (Division of Urban Forestry). Street trees in the public right-of-way are City property and always require a permit.

Key details: Code Section: ROH Ch. 40, Art. 8 (§§ 40-8.2 to 40-8.9). Exceptional Tree Permit: DPR Division of Urban Forestry. Removal Approval: City Council required. Max Fine: $1,000 per violation (ROH 40-8.8). Contact: (808) 971-7151, duf@honolulu.gov.

Under ROH § 40-8.8, anyone who removes or destroys an exceptional tree without Council approval, or alters its shape or branches without a DPR permit, is fined up to $1,000 per violation. Damaging street trees is independently unlawful and can result in code citations, restoration costs, and stop-work orders.

This is one of the stricter rules in Honolulu's municipal code. If you are unsure whether your situation complies, it is worth checking with the city before proceeding.

The Bottom Line

Honolulu's landscaping rules rules are a mixed bag. Some areas are strict, others are relaxed, and the details matter. The best approach is to check the specific rule that applies to your situation rather than assuming Honolulu is broadly strict or permissive.

This guide is based on Honolulu's current municipal code. Local rules can and do change, so check the individual ordinance pages for the latest details, penalties, and FAQs.