Portola Valley — Landscaping and Screening

Last reviewed: July 2, 2026

Overview

This page summarizes what the Portola Valley Zoning Ordinance requires for landscaping, screening, fences, walls, tree planting/removal, and buffers. It is based only on the town zoning/planning ordinance material retrieved from the Portola Valley code and points to the specific controlling code sections (the § citations) so applicants and reviewers can verify particulars. For matters outside the zoning ordinance text (for example, construction standards in the State code) see the linked resources below; where the ordinance is silent I note that fact.

(First-time links to related topics below are inline: see Portola Valley Zoning & Planning overview, Design Review, Development Standards, Overlay Districts, Parking, and ADUs. For state construction rules see California Building Standards Code.)

What the ordinance regulates (short list)

• Required planting in front yards for nonresidential uses and coordination of planting in certain commercial/professional districts — § 18.56.020 .
• Fence location limits, height limits, opacity and color reflectivity standards, and special rules for horse fences — § 18.43.020–080 and § 18.43.030–060 .
• Fence exceptions for non-residential districts and measurement rules for fences on retaining walls or fill — § 18.42.040 and § 18.43.030 .
• Creek setback planting guidance and limits on fences in creek setback areas — § 18.59.090–100 .
• Requirement for a planting plan as part of ASCC review and the ASCC’s authority to require landscape/screening measures — § 18.64.040 A.12 and § 18.64.060 D. .
• Special landscaping coverage (percent of parcel) requirements for C‑C and A‑P districts — § 18.56.020 E. .
• Definitions relevant to fences (e.g., domestic fence, horse fence) — § 18.04.129 / 18.04.215 (definitions) .

Below is a district-by-district breakdown (based on text found in the ordinance) focused on landscaping and screening rules.

District-by-district guidance (what the ordinance actually says)

Note: the ordinance uses a mix of named districts and parcel-size categories to set landscaping/fence rules. Where the code is silent about permitted uses for a district or full dimensional tables, state "Not found in retrieved materials" and refer you to the Town’s Zoning map and the Portola Valley Zoning overview.

• Residential (parcel-size categories used for fence/opacity rules)

  • Purpose / where it applies: All residential zoning districts as generally defined in the ordinance; fence standards are applied according to the parcel-size thresholds in the fence chapter. Not found in retrieved materials: a single consolidated list of R‑district names and permitted uses for each zoning designation (see Portola Valley Zoning for the map).
  • Key landscaping/screening requirements:
    • Domestic fences allowed in required yards for parcels with minimum area less than one acre; for parcels with minimum area one acre domestic fences are allowed but a front-yard domestic fence must be set back at least 25 feet from the front property line; for parcels with minimum area two acres or more, only horse fences are allowed in required yards — § 18.43.020.A.1–3 .
    • Fence height limits: 4 ft in front yards, 6 ft in side and rear yards, 4 ft along road rights-of-way side yards — § 18.43.030.B.1 .
    • Fence opacity limit for front yards: 50% opacity where applicable — § 18.43.040.A.1–2 .
    • Fence permit required for fences in required yards; small low fences (≤ 2 ft high and ≤ 20 ft total length) are exempt from permit but must meet other chapter rules — § 18.43.080.B .

• Mountainous‑Residential (M‑R)

  • Purpose / where it applies: M‑R is listed among residential-related districts; fences in the M‑R district are governed by the fence chapter provisions for residential districts — § 18.42.040.A and § 18.43 .
  • Key requirements: Same fence location/height/opacity and permit rules as other residential districts (see the Residential entry above). Not found in retrieved materials: additional unique M‑R landscaping matrices beyond fence references.

• Open‑Area (O‑A)

  • Purpose / where it applies: O‑A treated like other residential districts for fence rules; additional planting allowed in public rights-of-way for native plants (see Section 18.37.020.G) — § 18.42.040.A and § 18.37.020.G .
  • Key requirements: same fence standards as residential; planting recommendations for native grasses/ground covers in rights-of-way — § 18.43 and § 18.37.020.G .

• Community Commercial (C‑C)

  • Purpose / where it applies: nonresidential/commercial areas. The code requires coordinated planting and a minimum percent of parcel in natural vegetative cover or landscaped condition: 30% for C‑C — § 18.56.020.E.1 .
  • Key requirements:
    • In nonresidential districts, front yards must have planting conforming to roadside planting standards with at least 25% of the required front yard landscaped (minimum dimension 5 ft) — § 18.56.020.A .
    • Landscaping for contiguous C‑C parcels should be coordinated to present a unified appearance — § 18.56.020.C .

• Administrative‑Professional (A‑P)

  • Purpose / where it applies: professional/services zoning. A‑P parcels must maintain 40% of the parcel in natural vegetative cover or landscaped condition (not used for motor vehicles, buildings or paving) — § 18.56.020.E.2 .
  • Key requirements: same front-yard planting rule as other nonresidential districts (25% front yard planted) and contiguous-parcel coordination when in C‑C/A‑P — § 18.56.020.A,C,E .

• D‑R (Scenic Ridgeline combining district)

  • Purpose / where it applies: D‑R combining district rules for areas along Skyline Boulevard and scenic ridgelines include strict limits on vegetation removal and tree removal near the right-of-way; all trees planted in the combining district must come from the conservation committee’s approved list — § 18.30.030–040 .
  • Key requirements: very limited removal of vegetation within 100 ft of Skyline Boulevard (e.g., removal of vegetation >5% of parcel area is prohibited; removal of living trees over 12" circumference is restricted) — § 18.30.040.A–B .
  • Trees planted in the D‑R are required to be from the conservation committee list — § 18.30.030 .

• Other / Nonresidential front yards

  • For nonresidential zoning districts, required front yards must have planting conforming to any roadside planting standards adopted by the conservation committee and at least 25% of the required front yard must be landscaped with a minimum planting dimension of 5 ft — § 18.56.020.A .

Key standards — quick reference table

Practical guidance / interpretation (plain-English synthesis)

• If you are proposing a commercial or professional site plan (in C‑C or A‑P), plan early for large swaths of preserved or planted vegetation: 30% or 40% of the parcel, respectively, must remain vegetated and cannot be paved or built over; also expect the town to require coordinated plantings along contiguous lots — § 18.56.020.E, C .
• For homes and accessory structures, fences are tightly regulated by parcel-size thresholds. On typical suburban or smaller lots (minimum area less than 1 acre), domestic fences are allowed in required yards but must meet height, opacity and color reflectivity rules; plan for a 4 ft front-yard limit and 50% opacity where the code applies — § 18.43.020–040 .
• Any project subject to Architectural and Site Control Commission (ASCC) review must include a planting plan consistent with the town’s design guidelines and native-plant preferences; the ASCC can require additional screening, fencing or landscape modifications to mitigate impacts — § 18.64.040.A.12 and § 18.64.060.D .
• If your property is within the D‑R (ridgeline) area, expect far stricter limits on tree and vegetation removal and that any new trees planted must come from the conservation committee’s approved list — § 18.30.030–040 .
• Creek setbacks: fences and vegetation within creek setbacks are separately regulated; fences below the top of bank cannot be replaced except as part of approved bank stabilization measures — § 18.59.080–090 .

Checklist — what an applicant must include / satisfy for landscaping or screening review

• Show existing and proposed planting/landscape areas on the site plan; include dimensions and species list (planting plan consistent with town guidelines) — § 18.64.040.A.12 .
• Demonstrate compliance with parcel landscaping minimums if in C‑C (30%) or A‑P (40%) — § 18.56.020.E .
• If proposing fences in required yards, show fence location, materials, height, opacity and color reflectivity on plans; include elevation and opacity calculations — § 18.43.020–050 .
• If property is within a combining district (e.g., D‑R), include any required conservation-committee-approved plant/tree lists and show preservation areas — § 18.30.030 .
• If work occurs in or near a creek setback, include creek-bank stabilization design or show compliance with creek vegetation rules — § 18.59.080–100 .
• For projects requiring ASCC review (including many discretionary ADUs or expansions), be prepared to justify that landscaping/screening preserve neighbor privacy and mitigate impacts; the ASCC may require changes — § 18.64.060.D .
• Apply for a fence permit when required; provide notice to adjacent owners as required by the permit rules — § 18.43.080.A .

Risks & Ambiguities

Plain-English Summary

Portola Valley’s zoning code requires landscaped front yards for nonresidential sites, large amounts of preserved/landscaped area on C‑C and A‑P lots, specific limits on fence height, opacity and materials tailored to parcel size, and ASCC review of planting plans for discretionary projects; creek areas and the scenic ridgeline combining district carry extra planting and tree-protection rules — see the cited sections below for the exact rules (§ 18.56.020, § 18.43, § 18.59, § 18.64) .

Source References

• § 18.43.020–080 (Fences: location, height, opacity, horse fences, permits) — .
• § 18.43.030 (Fence height measurement and limits) — .
• § 18.43.040 (Fence opacity limits) — .
• § 18.43.050–060 (Color reflectivity; horse fence standards) — .
• § 18.43.080 (Fence permits & administration; notice and appeals) — .
• § 18.56.020 (Required landscaping: front yards, contiguous C‑C/A‑P planting coordination, parcel percent cover for C‑C/A‑P) — .
• § 18.59.080–110 (Creek bank stabilization, fences and vegetation in creek setbacks) — .
• § 18.64.040 & § 18.64.060 (ASCC review submittal items; planting plan requirement; ASCC findings including landscaping/screening) — .
• § 18.30.030–040 (D‑R combining district—tree/vegetation protections near Skyline Boulevard) — .
• Definitions (e.g., Domestic fence) § 18.04.129 — .

Retrieved passages

• Portola Valley Zoning Code (§ 1) High relevance show source text
• Portola Valley Zoning Code (§ 1) High relevance show source text
• Portola Valley Zoning Code (§ 3) High relevance show source text
• CWUIC § 65850.6 (Title 24) High relevance show source text
• Portola Valley Zoning Code (§ 1) High relevance show source text
• Portola Valley Zoning Code (§ 1) High relevance show source text
• Portola Valley Zoning Code (Section 18.59.090) High relevance show source text
• Portola Valley Zoning Code (§ 3) High relevance show source text

Cited sections

• **§ 18.43.020–080** (Fences: location, height, opacity, horse fences, permits) — . (§ 18.43.020)
• **§ 18.43.030** (Fence height measurement and limits) — . (§ 18.43.030)
• **§ 18.43.040** (Fence opacity limits) — . (§ 18.43.040)
• **§ 18.43.050–060** (Color reflectivity; horse fence standards) — . (§ 18.43.050)
• **§ 18.43.080** (Fence permits & administration; notice and appeals) — . (§ 18.43.080)
• **§ 18.56.020** (Required landscaping: front yards, contiguous C‑C/A‑P planting coordination, parcel percent cover for C‑C/A‑P) — . (§ 18.56.020)
• **§ 18.59.080–110** (Creek bank stabilization, fences and vegetation in creek setbacks) — . (§ 18.59.080)
• **§ 18.64.040 & § 18.64.060** (ASCC review submittal items; planting plan requirement; ASCC findings including landscaping/screening) — . (§ 18.64.040)
• **§ 18.30.030–040** (D‑R combining district—tree/vegetation protections near Skyline Boulevard) — . (§ 18.30.030)
• Definitions (e.g., **Domestic fence**) **§ 18.04.129** — . (§ 18.04.129)
• PortolaValley_ZoningCode.md

• Official Portola Valley code library