Chapter 4 – landscape guidelines

4.0  Landscape Vision

The landscape vision for TNC strives first and foremost to respect and emulate the small-town feel and rural character indicative of the Paso Robles region.
The goal of landscape design is to create signature landscapes and a community that is pedestrian-friendly, aesthetically coherent and environmentally sensitive; a desirable place to live, learn and play, and known for its distinctive small-town friendliness and rural character. The following objectives define the sustainable landscape vision of TNC:
Aesthetics
Create a coherent design aesthetic and identity for the community through a regionally sensitive landscape design.
Environment
Provide the infrastructure necessary for the responsible use and treatment of natural resources, through sustainable technologies which prove themselves reliable and effective in achieving sustainable site development.
Open Space
Preserve, enhance or create open spaces that are regionally compatible, support native species, preserve existing oak trees, accessible and inspiring places to be.
Safety and Well-Being
Create a sense of safe and welcoming pedestrian environments, through the use of traffic calming, continuous trail systems, recreational amenities and effective site and landscape design.

4.1  Sustainable Landscape Principles

The following principles have been established to support a healthy balance of environmental, social and economic vitality for sustainable landscape design. The intent is to serve as a guide and also to remain flexible to allow for implementation of future technologies as they prove themselves reliable.
Use Sustainable Materials
Sustainable materials should be used in the landscape construction and site furnishing selections including, but not limited to, recycled materials, environmentally preferable products, materials that can be recycled, certified “green” products and locally available or manufactured products.
Protect and Select Appropriate Vegetation
Existing oak trees shall be protected in place to every extent possible, during construction and to ensure future longevity beyond project completion. Plant materials should be selected based on their reduced need for water, fertilizers, pesticides and maintenance. Plants should be selected to meet aesthetic goals, mature plant size, potential to provide habitat and their ability to thrive in their intended locations. They may include native drought tolerant and Mediterranean species.
Design Based on Size at Maturity
Landscape designs and plant spacing shall allow for plants to reach mature size. Using appropriately size and placing of plants prevents overgrowth and future thinning reducing the amount of material sent to the landfill. Plants should be carefully located to ensure proper drainage and to reduce potential damage to buildings.
Protect the Soil
Soils from the site should be re-used, if appropriate, as horticultural soils. Maintain and/or improve soil health through responsible management and restoration to sustain protected and future ecosystems.
Reduce Water Use
Reduce potable water use in the landscape through the use of existing on-site irrigation wells or use of recycled water where feasible, high efficiency irrigation systems and drought tolerant plant selections. Irrigation design shall utilize weather and climate-smart controllers, irrigation zones to suit plant requirements and high-efficiency nozzles.
Optimize the Ecological Benefits of Storm Water Drainage
Storm water drainage should be managed through current best practices with the goal of maintaining and enhancing the pre-development hydrology, through the implementation of Low Impact Development strategies. In conjunction with the drainage infrastructure, landscape treatments shall assist in providing for bioretention, aesthetic enhancement and potential habitat.
Suitable elements may include bioswales and/or pervious pavement where suitable for site conditions. Bio-swales shall be swaled drainage courses and filled with appropriate vegetation or locally supplied riprap. See section 6.1.1.G for example location.
Plants should be selected to withstand extreme wet and dry conditions, tolerance for potential contaminants found in roadways, and be located appropriately to allow for desired drainage flows.
Promote Human Well-Being
Ensure connectivity throughout the project site with opportunities for varying scales of activity and interaction. Way-finding devices and site features shall provide interest, aid orientation and instill community pride.

4.1.1  Local Food Production

Local food integrates production, processing, distribution and consumption on a small scale, creating sustainable local economies and a strong connection between farm and table. At TNC, local food production will be encouraged and suitable square footage is provided in the combined area of private yards and common community gardens. The Agricultural Plant Palette also provides a guide for appropriate plant selections to implement private farms at any scale. 

4.2  Landscape Themes

The  landscape themes for TNC are drawn from the natural plant communities which currently shape the Paso Robles area. The specific themes serve as a guide for the landscape design and plant selections with the primary goal of integrating TNC into the surrounding landscape while establishing a signature identity and sense of place.

4.2.1  Oak Woodland

The Oak Woodlands are the most predominant link to Paso Robles and the true icon of this community. All existing on-site Oak trees will be preserved. Signature Oak trees should mark major entries as well as grace the rolling hillsides above. The Oak Woodland plant community will be prevalent among the residential neighborhoods to naturally and visually anchor the homes to the rolling hills. Oak Woodlands consists predominantly of Oak, Madrone, California Bay Laurel trees, with an understory of drought-tolerant, Mediterranean shrubs and groundcovers. Perennial color will also provide interest with pinks, white and purples of Coral Bells and many varieties of Sage.

4.2.2  Riparian

The Salinas River corridor provides a natural buffer and wonderful amenity for TNC. Existing riparian plant community characteristics within TNC should remain in place and serve as a model for adjacent and future riparian themed areas. The riparian plant communities could also be extended into other man-made water bodies, detention basins and drainage corridors to provide a visual link to the existing site character. This theme is recognized by signature Sycamore and Arroyo Willow trees; supported by a textured mix of flowering shrubs, bold leaf forms and upright grasses. The riparian theme can be accomplished in the neighborhoods and recreational zones using drought tolerant varieties which offer similarly bold and diverse textures.

4.2.3  Chaparral

The chaparral theme represents one of the most diverse of the plant communities; able to withstand dry summers, cold winters and shallow, clay soils. These conditions make chaparral most recognizable as the native hillsides of California. Rolling mounds of olive, blue and grey-green foliage are punctuated by ornamental grasses and perennial color with typical flower displays of yellow, blue and purple. Signature trees should visually connect to the neighboring plant communities with predominantly Sycamore, Oak and California Bay Laurel.

4.2.4  Agrarian

Inspired by the Paso Robles history and current, burgeoning wine industry, agriculture continues the tradition as a major presence in TNC. Community open space shall double as an outdoor classroom and a rhythmic display of classic vineyards. The implementation of edible landscapes and private farms is also encouraged in the private realm of side yards and rear yards.

4.3  Edge Conditions

With respect to goals described in the Gateway Design Plan for the City of Paso Robles, the edge design treatment for TNC should make every effort to preserve and enhance attractive and appropriate transition areas from residential neighborhoods to the “countryside” while preserving all existing Oak trees.

4.3.1  River Bluff Edge

The western boundary of TNC is alive with the thriving Salinas River riparian corridor. The existing diversity and density of plant material makes for an effective boundary in conjunction with the dramatic topographic changes.

4.3.2  Vineyard Edge

As part of an agriculture buffer to adjacent vineyards, TNC will have a 300-foot buffer from the existing vineyard to effectively transition into the Special District and Neighborhood Zones. Travel along North Vineyard Road, the northern boundary, will be designed and planted to be consistent with a “country” experience. Planting of vineyards in this area will screen neighborhood development from North Vineyard Road.

4.3.3  Rural Estate Edge

Buena Vista Drive marks the eastern boundary of TNC and provides a distinct border between the neighborhood edge zone and the existing low-density estates to the North and between the future Cuesta College development and the most eastern neighborhood (neighborhood 8) to the South. A 10-foot wide multi-use decomposed granite (DG) path, bordered by landscaped areas on both sides shall create a softened transition. Essentially, this linear park will visually reinforce the pedestrian-friendly and regionally compatible goals of TNC.
Additionally, the transition between TNC residential on the eastern-most parcel along Buena Vista will be softened by a 20-foot landscape buffer and 70-foot density buffer. This will allow development to step down from potentially 3-story buildings, to 2-story along the edge, gradually transitioning into the landscape character of existing development.

4.3.4  Existing River Oaks Edge

The southern boundary of the project site will create a seamless transition from existing River Oaks to future TNC development. Circulation systems shall continue without interruption to connect existing residents with future neighbors and community amenities.

4.4  Village Elements

4.4.1  Open Space

Open space designated areas will consist of protected habitat and riparian corridors, passive and active recreation opportunities and organic vineyards.
The Paso Robles area has developed into an important wine region where vineyards now occupy a vast portion of the rolling hills surrounding the community. To connect with the agricultural character, the upper slopes and open space of the TNC community will also serve as a working sustainable vineyard. The views towards open space and vineyards shall be maintained to provide a sense of place and strong connection with the natural environment.

4.4.2  Streetscape

Parkways and front yards will utilize mixed shrubs, grasses and groundcovers to both visually tie to nearby native plantings and reduce water needs. Plant selections shall be consistent with the Landscape Theme Master Plan. Ornamental turf areas will be reserved for recreational or special event areas only. The heat-island effect will be further mitigated through the use of shade trees and/or shade structures along pedestrian pathways.

4.4.3  Fences and Walls

Fences and walls shall provide continuity throughout the different neighborhoods and should be compatible with the rural character of the planning area.
•   Some appropriate wood and clear-view fence types include split rail, tubular steel pickets and those shown above. Landscape features, such as climbing vines are encouraged on any of these fence types.
•   Security fencing shall be constructed of open materials, not solid walls. Steel picket and wood board fencing are acceptable for security fencing.
•   Front-lot fencing shall be no taller than 36 inches, rear and side-yard fencing no taller than 6 feet.
•   Except where property lines are adjacent to open space, fencing shall be no taller than 3-4 inches high and be of open-rail style, constructed of wood or other acceptable material.
•   A detailed fence plan shall be submitted to the City at the time of application for development.
Retaining walls shall provide continuity between the existing River Oaks and TNC.
•   Retaining walls shall have finish materials of decorative block, brick or stone veneer.
•   A landscape buffer with a minimum width of 5 feet shall be established at the base of any retaining wall exceeding 42 inches in height.
•   A detailed wall plan shall be submitted to the City at the time of application for development.
•   Where privacy walls are used, materials and construction should be designed to complement the design of the larger area rather than individual units.

4.4.4  Site Furnishings and Light Fixtures

Site furnishings and light fixtures reflect an extension of the existing River Oaks elements to establish continuity and connectivity. Furniture should be provided throughout the community to allow for opportunities for residents and visitors to gather. Street lights and parking area lights will include the single curved wood pole consistent with the existing River Oaks development.

4.5  Irrigation Guidelines

The design and construction of irrigation systems shall ensure water is conserved to the maximum extent possible.
A.  Controllers and Valves
Irrigation systems should include automatic, “Smart” controllers equipped with historic weather data, satellite link or other external sensors. All plants shall be grouped by similar and appropriate hydrozones and have a dedicated valve for each zone.
B.  Distribution Uniformity
The irrigation system should utilize high performance equipment and proper scheduling. Good distribution uniformity will help ensure water is evenly applied across an area and limit potential for the over or under-watering of different areas. The system should achieve 70% distribution uniformity or greater for turf areas and 80% in all other landscaped areas.
C.  Low Volume Irrigation
Non-turf, shrub areas should be irrigated with low-volume micro-spray or point application devices.
D.  Mulch
All exposed soil surfaces of non-turf areas shall be covered with a layer of organic mulch to a minimum depth of 2 inches.
E.  Turf Irrigation
Turf areas shall be irrigated with equipment that has a precipitation rate of 1 inch or less per hour. Stream rotator heads are preferred; use of standard spray heads should be avoided.
Turf areas less than 8 feet on the shortest side shall be irrigated by a subsurface method or micro-spray heads to avoid overspray.
F.   Non-Potable Water
Irrigation water supply should be serviced by separate irrigation water meters and non-potable water sources as those sources become available. Non-potable water is currently available from existing on-site irrigation wells. Non-potable water sources may also become available through reclaimed water from the City of Paso Robles as such sources are developed. Infrastructure shall include purple pipe for when non-potable water becomes available. In the event well water is used, water samples shall be analyzed to determine appropriate plant selections.

4.6  Plant Palette

Landscape and planting of all common and private areas within TNC shall be subject to the following approved plant palettes by landscape theme area. To preserve the quality of TNC and the surrounding area, invasive plants not suitable for the local climate are prohibited. All plants listed in the County Potentially Problematic Plant List are prohibited within TNC.
The following plant palette provides a suggested list for use throughout TNC. The palette is divided by landscape themes and is intended as a guide, in conjunction with the Landscape Theme Master Plan, for planting designs throughout the public realm. Streetscapes, parkways and front yards shall adhere to the landscape themes while rear and side yard applications are permitted to select a variety plants from the different themes. This list may be expanded upon as new cultivars are developed by the nursery industry and as additional species prove themselves reliable in the TNC location. Planting designs shall respond to County of San Luis Obispo recommendations noted in the “County Potentially Problematic Plant List” and avoid use of potentially invasive species.

4.6.1  CHAPARRAL PLANT PALETTE

General Design Concept:
•   Naturalized
•   Generous plant massings in rolling mounds
•   Punctuated by ornamental grasses and perennial color
•   Grey, Blue and Olive Greens with purple, yellow and white color.

4.6.2  RIPARIAN PLANT PALETTE

General Design Concept:
•   Naturalized
•   Bold texture and diversity
•   Meandering
•   Dark and Blue-Greens with upright ornamental grasses

4.6.3  OAK WOODLAND PLANT PALETTE

General Design Concept:
•   Naturalized
•   Dense tree and shrub cover
•   Habitat
•   Dark olive and grey-greens punctuated by bright perennial color

4.6.4  AGRICULTURAL PLANT PALETTE

General Design Concept:
•   Outdoor Classroom
•   Organic
•   Sustainable Gardening
•   Connect residents to food sources