Chapter 17.25 — LANDSCAPING

Sections:

• 17.25.010 Purpose.

• 17.25.020 Applicability.

• 17.25.030 Xeriscape principles.

• 17.25.040 Areas to be landscaped. 17.25.050 Requirements.

This chapter establishes minimum standards for the provision, installation, and maintenance of landscape areas by the following means:

• A. Promote the conservation of potable and nonpotable water by encouraging the preservation of existing plant communities, implementing xeriscape principles, encouraging the use of site-specific plant materials, and establishing techniques for the installation and maintenance of landscape materials and irrigation systems.

• B. Improve the appearance of all open areas through the incorporation of open space into development in ways that harmonize and enhance the natural and built environment.

• C. Improve environmental quality by recognizing the numerous beneficial effects of landscaping upon the environment, including:

  1. Improving air and water quality through such natural processes as photosynthesis and mineral uptake;

  2. Maintaining permeable land areas essential to surface water management and aquifer recharge;

  3. Reducing and reversing air, noise, heat and chemical pollution through the biological filtering capabilities of trees and other vegetation;

  4. Promoting energy conservation through the creation of shade;

  5. Reducing heat gain in or on buildings or paved areas;

  6. Reducing the temperature of the microclimate through the process of evapotranspiration; and

  7. Encouraging the conservation of limited fresh water resources through the use of site-specific plants and various planting and maintenance techniques.

The St. Helena Municipal Code is current through Ordinance 26-4, passed May 12, 2026.

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D. Maintain and increase the value of land by requiring landscaping to be incorporated into development, thus becoming by itself a valuable capital asset.

• E. Minimize or eliminate conflicts between potentially incompatible uses through landscaping.

• F. Provide direct and important physical and psychological benefits to human beings through the use of landscaping to reduce heat and glare, and to break up the monotony and soften the harsher aspects of urban development.

G. Preserve existing natural vegetation and promote the incorporation of native plants, plant communities, and ecosystems into landscape design, where possible.

H. Promote innovative and cost-conscious approaches to the design, installation and maintenance of landscaping, encouraging water and energy conservation.

I. Establish procedures and standards for the administration and enforcement of this section. (Ord. 23-4 § 5 (Exh. A))

• A. The provisions of this chapter shall apply to the following:

  1. New construction and rehabilitated landscapes for public agency projects and private development projects with a landscape area equal to or greater than two thousand five hundred (2,500) square feet requiring a building permit or major design review;

2. New construction and rehabilitated landscapes in single-family and multifamily residential projects with a landscape area equal to or greater than two thousand five hundred (2,500) square feet requiring a building permit, landscape permit, or major design review; or

   3. Existing landscape areas over one acre in size.

• B. This chapter does not apply to:

  1. Registered local, state or federal historical sites;

  2. Ecological restoration projects that do not require a permanent irrigation system;

  3. Mined-land reclamation projects that do not require a permanent irrigation system; or

  4. Plant collections, as part of botanical gardens and arboretums open to the public. (Ord. 23-4 § 5 (Exh. A))

The St. Helena Municipal Code is current through Ordinance 26-4, passed May 12, 2026.

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The following xeriscape principles serve as the primary means of achieving water conservation:

• A. Design of the landscape by dividing it into high-, moderate,—and low-water use zones and by taking advantage of microclimates caused by the different conditions of sun, slope, moisture and air movement (hydrozones);

• B. Efficient irrigation systems;

• C. The use of soil amendments to improve the water-holding capacity of the soil;

• D. Limiting turf to locations where it provides functional benefits;

• E. The use of mulches, where appropriate;

• F. Selection of appropriate plants; and

• G. Maintaining the landscape appropriately (monitor the irrigation system and water according to needs). (Ord. 23-4 § 5 (Exh. A))

The following areas shall be landscaped and may count toward the total area of the site required to be landscaped by the zoning district regulations:

• A. Required Setbacks. All required front and street-facing side setbacks, except for areas used for exit and entry, shall be landscaped.

B. Interior Property Lines Abutting Residential Districts. Whenever a nonresidential use is located adjacent to a residential district or use, a landscape buffer planted with a mix of trees and shrubs shall be provided along interior property lines. At least one tree of at least fifteen (15) gallon size shall be planted per twenty (20) linear feet or as appropriate to create a tree canopy over the buffer. In addition, at least three shrubs shall be planted per twenty (20) linear feet.

1. SC, BPO, and I Districts. Landscaped buffer six feet in width.

2. Other Nonresidential Uses. Landscaped buffer four feet in width.

C. Building Perimeters. The portions of a nonresidential building that front a public street shall have one or more landscape planters installed along a minimum twenty percent (20%) of that building face. The minimum width of the planter shall be three feet. This standard does not apply to buildings facing Main Street within the Historic Overlay district and buildings located on the front or corner side property line.

The St. Helena Municipal Code is current through Ordinance 26-4, passed May 12, 2026.

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D. Landscaping Requirements on Flag Lots. Landscaping is required in the panhandle portion of all flag lots (i.e., an easement or if owned) alongside the driveway.

E. Unused Areas. All areas of a project site not intended for a specific use, including areas planned for future phases of a phased development, shall be landscaped or hydroseeded. The community development director may waive this requirement for areas planned for future development. (Ord. 23-4 § 5 (Exh. A))

A. Model Water Efficient Landscaping Ordinance (MWELO). Landscaping shall be consistent with the state of California’s MWELO, which is found at Sections 490 to 495 of Chapter 2.7, Division 2, Title 23, of the California Code of Regulations.

B. General Requirements. In all areas where landscaping is required in accordance with Section 17.25.040, Areas to be landscaped, landscaping shall be permanently maintained by the property owner in accordance with the following standards:

1. Shade Tree Species. Shade trees shall be of a variety approved by the city that will, under ordinary circumstances and growing conditions, provide shade upon reaching maturity.

2. Tree Distribution. Distribution of trees shall generally be in a grid or similar pattern or exhibit a regular spacing within off-street parking lots, required setbacks, and other open spaces and landscaped areas.

3. Incidental Features. Landscaping may include incidental features such as stepping stones, benches, fountains, sculptures, decorative stones, or other ornamental features, placed within a landscaped setting.

4. Gardens. Garden areas and other areas dedicated to edible plants are considered landscaped areas and count toward required landscaping.

5. Turf. No more than twenty-five percent (25%) of the landscaped area may be turf. If the turf is irrigated with reclaimed or greywater, this percentage may be exceeded, as determined by the public works director.

6. Gravel Surfaces and Pavers. Landscaped areas may include graveled surfaces and surfaces paved with pavers, provided they do not cover more than thirty percent (30%) of the area required to be landscaped.

   7. Invasive Plants Prohibited. Plant species that are listed by California Invasive Plant Council (Cal-IPC) as invasive are prohibited. Existing invasive plants and noxious weeds shall be removed.

• C. Specific Requirements.

1. CB and MU With Main Street Frontage. The following standards apply to all parcels with frontage on Main Street in the CB and MU districts:

a. Landscaping Not Required. Where buildings are located at the back of the sidewalk on the property line or within two feet of a property line, no landscaped areas are required. Instead the sidewalk must be

The St. Helena Municipal Code is current through Ordinance 26-4, passed May 12, 2026.

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extended to the front of the building and constructed with materials that match the surface of the existing sidewalk.

b. Parking Areas. Unless otherwise specified in this chapter or under the conditions of an approved permit, planted areas shall have a width of not less than four feet and shall be protected from vehicles where necessary through the provision of barriers or tire stops.

2. All Other Areas. The following standards apply to all areas not described in subsection (C)(1) of this section:

a. Dimension of Landscaped Areas. No landscaped area smaller than three feet in any horizontal dimension shall count toward required landscaping.

b. Parking Lot Trees. All trees in parking lots shall be a minimum fifteen (15) gallon can size and shall conform to the National Association of Nurserymen’s adopted standards for growth, condition and development of nursery-supplied materials. Modification of these standards for equivalent quality of tree or shade plant may be permitted depending on the species. The following minimum number of trees in Table 17.25.050(A): Parking Lot Trees Required, shall be required in any parking lot:

Table 17.25.050(A). Parking Lot Trees Required

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Parking Lot Size Number of Trees
15 spaces or fewer 1 tree/4 spaces (minimum of 2 trees)
20 trees/acre if canopy is 40 feet or greater
16 spaces or more
24 trees/acre if canopy is less than 40 feet
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c. Planters. Where a parking lot abuts a public right-of-way, there shall be provided a landscaped planter that is a minimum three feet in width and parallel to the right-of-way.

d. Curbing. In all areas where vehicular circulation is permitted, landscaping and shade trees shall be contained in planters and tree wells bordered by a six-inch-high concrete curb or equivalent barrier approved by the city.

e. Width and Protection. Unless otherwise specified in this chapter or under the conditions of an approved permit, planters and tree wells shall have a width of not less than five feet and shall be protected from automobile overhang where necessary through the provision of barriers, tire stops, or additional width.

D. Maintenance. All planting and other landscape elements shall be maintained in good growing condition. Such maintenance shall include, where appropriate, pruning, mowing, weeding, cleaning, fertilizing, and regular watering. Wherever necessary, plantings shall be replaced with other plant materials to ensure continued compliance with applicable landscaping requirements.

E. Irrigation. Landscaped areas and planters shall be served by an irrigation system approved by the city and shall be kept in a weed-free condition.

The St. Helena Municipal Code is current through Ordinance 26-4, passed May 12, 2026.

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F. Landscape Documentation Package. For any project subject to this section, a landscape documentation package shall be submitted to, reviewed by, and approved by the community development director prior to the issuance of any building permit or the replacement of landscaping. The landscape documentation package shall include all required information as established in the state MWELO guidelines or successor regulations.

G. Amendment of Approved Plan. Any significant change of plant material, size or design from that contained in an approved landscaping plan shall require the approval of a revised landscaping plan reviewed in the same manner as the original plan. The community development director may determine on a case-by-case basis what is a significant change to an approved landscaping plan. (Ord. 23-4 § 5 (Exh. A))