Ocean-Friendly Gardening

Whether you live five miles—or fifty—from the coast, 
your landscape impacts ocean health.

For most gardeners, the first rains after the dry season are cause for celebration. But talk to a watershed activist and you’ll hear it’s not all good news. That first inch of rain, or “first flush,” contains high concentrations of pollutants that have built up since the last rainy season ended.

sloping rock garden overlooking ocean

Automobile engine oil, exhaust and brake pad dust, pet waste, garden pesticides, herbicides, fertilizers, and sediment all join with the rainwater as it runs off our properties and roads and into storm drains that eventually feed into the ocean. Except for a few towns, stormwater goes to the Pacific without being treated. Once it enters coastal water, untreated stormwater causes ocean acidification and red tides that kill marine populations and could eventually lead to the extinction of certain sensitive species. Untreated runoff poisons the water and its inhabitants, but it is also of concern to those of us who enjoy surfing, swimming, and fishing. In older cities like San Francisco, where stormwater and sewer systems are combined, heavy rains can cause untreated sewage to overflow into the ocean.

The threat extends beyond the rainy season. On sunny weekends, car washing and poorly designed or broken sprinkler heads spray water onto dirty, impermeable urban surfaces, creating what is called “dry-weather runoff.”

Carex praegracilis in a San Luis Obispo garden

The Surfrider Foundation has developed a program they call Ocean Friendly Gardens (OFG) that looks at urban landscapes as both the origin of pollution and a part of the solution. Ocean Friendly Garden developers encourage us to apply “CPR” to our gardens. Here’s how the OFG website breaks it down:

• Conservation of water, energy, and habitat through native and climate-adapted plants, spaced for mature growth, using the most efficient irrigation system to supplement rainwater use.

• Permeability through mulch and biologically active soil and using permeable materials for—or making cuts in existing—driveways, walkways, and patios that allow water to percolate into the soil.

• Retention devices like swales or dry stream beds slow down and soak up rainwater in the soil preventing it from rushing off of the property. Rainbarrels, with overflows to the landscape, provide water during dry months.

Verbena bonariensis above yellow flowering Achillea varieties

In areas with mediterranean climates like California, these measures have the added benefit of complying with recent legislation (Water Efficient Landscape Ordinance, Assembly Bill 1881) that requires most new landscapes and redevelopment to prevent dry-weather runoff and develop water budgets. Ocean Friendly Gardens, therefore, serve to protect waterways as well as reduce green waste, trim expensive and unnecessary water use, and have an overall smaller carbon footprint.

Here in coastal San Luis Obispo County, local landscape contractor and Surfrider member Robert Nieto has been designing and retrofitting OFGs with breathtaking results using colorful mediterranean plants and succulents that maximize beauty and enjoyment in gardens overlooking the cliffs of Shell Beach.

The biggest challenge to creating an OFG, he explains, is getting people to change their idea of what a garden should be. A front yard doesn’t need to be carpeted with a trim green lawn, and shrubs don’t need to be pruned into neat geometrical shapes. Why not plant a meadow of native grasses and select shrubs that can be appreciated for their natural architecture—any Arctostaphylos would surely impress.

Leucadendron ‘Safari Goldstrike’ and Rosmarinus ‘Irene’ share the frame with Garrya elliptica, Otatea acuminata ssp. aztecorum, and Leucadendron ‘Winter Red’

Nieto also encourages his clients to view their yards as ecosystems. This means that whoever does the garden maintenance (be it the homeowners or a hired gardener) will need to be an environmental steward who is attentive to the ecology of the space; the old “mow and blow” routine will simply not work. Payoffs to this maintenance approach are numerous. Permeable pathways and truckloads of mulch keep water on-site. Structural pruning will improve the long-term health of plants, water bills will shrink, and families can enjoy watching the 
native wildlife that visit the yard once the interruption of noise- and air-polluting equipment is gone.

Verbena lilacina ‘De La Mina’

Surfrider has created a suite of educational activities from neighborhood walks to in-room classes and hands-on garden parties, and has teamed up with professionals such as G3/Green Gardens Group to conduct workshops for residents and homeowners, industry professionals, government agencies, and teachers. An underlying goal of the program, according to Surfrider OFG Coordinator, Paul Herzog, is “more hands-on training and fewer handouts.” With OFG training, residential property owners might decide to do the work themselves or feel more comfortable hiring a professional, government agency reps will be better equipped to understand their customer’s needs, and landscape professionals can lead ocean-friendly projects at homes, schools, and city parks. Everyone working as a team means people hear a consistent message, supported by multiple resources. It’s the domino effect of good gardening.

For those of us who aren’t ready to completely redesign our landscape, the following small steps make any coastal garden more ocean friendly.

• Consider installing smart controllers that initiate irrigation based on actual weather and evapotranspiration rates.

• Redirect downspouts from connecting to municipal stormwater or sewer systems so water stays on-site in the garden.

• Mulch bare soil with fallen leaves to retain soil moisture and feed microorganisims.

By: Hallie Schmidt, PacificHorticulture: http://www.pacifichorticulture.org/

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