How Ontario Handles Landscaping Rules: A Practical Guide

Ontario maintains 126 local ordinances across all categories, and 7 of those deal specifically with landscaping rules. Here is a breakdown of what the city actually requires, what is prohibited, and where Ontario falls on the strict-to-permissive spectrum compared to other cities.

Artificial Turf

Ontario allows artificial turf at homes subject to drainage and zoning rules. Civil Code 4735 (AB 349) blocks HOA bans, and AB 1572 makes synthetic turf a compliant replacement for commercial non-functional turf.

Key details: City status: Allowed with drainage and zoning check. HOA protection: Civil Code 4735 (AB 349). AB 1572 alternative: Qualifies to replace non-functional turf. Permit: Usually none for at-grade residential. Front yard: Subject to planted-area minimums.

Improper drainage that causes water to discharge onto neighboring property or the public right of way can be cited as a nuisance. Installations that exceed front-yard paving caps or violate zoning setbacks require correction under a Code Enforcement notice.

Ontario is more permissive than most cities when it comes to artificial turf. That said, there are still limits.

Rainwater Harvesting

California's Rainwater Capture Act (AB 1750) lets Ontario residents collect roof rainwater for outdoor use without a permit for simple barrels. Large cisterns and indoor use require plumbing permits.

Key details: State law: Rainwater Capture Act (AB 1750). Small barrels: Generally no permit. Large cisterns: Plumbing permit required. Indoor use: Permit and backflow device. Mosquito control: Screen all openings.

Unpermitted pressurized or indoor rainwater systems can trigger a stop work order and required correction. Mosquito breeding violations are cited by San Bernardino County Mosquito and Vector Control rather than the city.

Composting

Ontario Municipal Code Section 6-3.501 lets residents compost yard trimmings and vegetable scraps at home, provided the pile sits in the rear or side yard, out of street view, capped at five feet in every dimension, at least five feet from the property line, and kept free of odor, rodents, insects, and runoff onto neighboring land.

Key details: Allowed materials: Yard trimmings, wood ash, veggie scraps. Excluded: Household refuse, animal wastes. Max size: 5 ft high x 5 ft wide x 5 ft long. Placement: Rear/side yard, hidden from street. Setback: 5 ft from property line, or solid wall.

The code does not set out a stand-alone fine schedule within Section 6-3.501 itself; a pile that violates the size, placement, odor, pest, or runoff conditions, or that sits at a location the Fire Department has flagged as a fire hazard, falls outside the composting authorization and can be treated as a violation of the surrounding Integrated Solid Waste Management chapter's general enforcement provisions.

Tree Removal & Heritage Trees

Removing or relocating any City parkway tree in Ontario requires prior authorization from the Public Works Agency under Municipal Code Sec. 10-2.06. Removal is limited to five listed grounds: a visual hazard, a safety hazard, disease or decay beyond correction, an unauthorized original planting, or clearing space for a solar collector installation.

Key details: Authorization required from: Public Works Agency. Allowed grounds: Visual/safety hazard, disease, unauthorized, solar. Solar removal notice: 30 days advance written notice. Condition-based removal: City must replace when feasible. Correction window: 48 hours after written notice.

Removing or relocating a parkway tree without Public Works Agency authorization violates Sec. 10-2.06, and Sec. 10-2.11 treats any uncorrected violation as a separate daily offense once 48 hours have passed after written notice, with penalties under Title 1, Chapter 2 of the Municipal Code. The City may also correct the violation itself and bill the owner for the cost.

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

Weed Ordinances

Ontario Municipal Code Chapter 6-9 (Weeds and Refuse Abatement) declares it unlawful and a public nuisance for any property to allow weeds, rubbish, refuse, or dirt to exist on it (Sec. 6-9.02). The City defines weeds to include brush that becomes a fire menace when dry, and abates non-compliant lots at the owner's expense, with unpaid costs becoming a special assessment on the property tax bill.

Key details: Code chapter: Ontario MC Ch. 6-9 (Weeds and Refuse Abatement), Sec. 6-9.01 to 6-9.15. Nuisance declaration: Sec. 6-9.02(a). Notice of Violation fee: $172 (Aug. 2025). Civil penalty: $500. Abatement cost: Actual contractor cost + $57 admin fee.

After a Notice of Violation, an owner who fails to abate is subject to City abatement of the nuisance, with the cost (including administrative and investigative costs) assessed against the property and constituting a personal obligation of the recipient (Sec. 6-9.02(b)). Program fees as of August 2025 include a $172 Notice of Violation, a $172 re-inspection fee, $500 civil penalties, and actual contractor abatement costs plus a $57 administration fee; unpaid amounts become a special assessment on the property tax bill, and a property may be sold by the tax collector after three or more years of delinquent assessments.

If you are coming from a city with tighter rules, you will find Ontario gives residents more flexibility on weed ordinances.

Tree Trimming

Ontario Municipal Code Sec. 7-3.13 makes the abutting property owner responsible for watering, trimming, and maintaining parkway vegetation, including trimming trees to a minimum clearance of eight (8) feet from grade. Planting or removing any parkway tree requires a City permit and must conform to the Master Plan of Parkway Trees; major pruning and tree surgery are handled by the City.

Key details: Code section: Ontario MC Sec. 7-3.13 (Landscaping parkways). Tree clearance: Minimum 8 feet from grade. Owner duty: Water, trim, and maintain abutting parkway vegetation. City duty: Median parkways, major pruning, tree surgery, high pruning. Tree planting/removal: City permit; conform to Master Plan of Parkway Trees.

Under Sec. 7-3.20, failure to comply with a notice of violation within forty-eight (48) hours is itself a violation, and each day of continued noncompliance is a separate offense. Where a violation is an immediate hazard, the City may eliminate it and recover the costs from the owner; the City may also correct the condition and levy the costs against the property when the owner fails to respond.

Water Restrictions

Ontario is in the Voluntary Conservation Stage of its Water Conservation Plan (Ontario Municipal Code Chapter 8A, sections 6-8.20 through 6-8.35). The City's WaterWise program asks residents to avoid watering lawns between 6:00 AM and 6:00 PM, prevent irrigation runoff, and stop hose-washing of paved surfaces; mandatory restrictions take effect only if the City Council declares a Stage 1 through Stage 6 shortage.

Key details: Code chapter: Ontario MC Ch. 8A (Water Conservation Plan), Sec. 6-8.20 to 6-8.35. Current stage: Voluntary Conservation Stage (no drought declared). Suggested no-water hours: 6:00 AM to 6:00 PM. Mandatory stages: Stage 1 (10%) through Stage 6 (50%+). Declaring authority: City Council (Sec. 6-8.22).

In the Voluntary Stage the WaterWise measures are requests, not enforceable mandates. If the City Council declares a Stage 1 through Stage 6 shortage, sections 6-8.33 and 6-8.34 authorize enforcement, including penalties and an appeal/hearing process; exceptions for recycled water and public-health uses are preserved under section 6-8.24.

If you are coming from a city with tighter rules, you will find Ontario gives residents more flexibility on water restrictions.

The Bottom Line

Compared to many U.S. cities, Ontario gives residents more room on landscaping rules. 3 of the 7 rules here are rated permissive. But permissive does not mean unregulated. There are still requirements, and the city does enforce them when violations are reported.

These rules come from Ontario's publicly available municipal code. For complete penalty schedules, exemption details, and answers to common questions, see the individual ordinance pages throughout this guide.