Gardening Practices to Enhance Creek Health

September 25, 2004

By Dale Norrington, Master Gardener

At the approach of rain it may behoove to remember that cumulatively, gardening practices throughout a watershed can significantly affect the health of local creeks. Lawn and garden runoff, as well as that from rooftops, driveways, walkways and patios, typically washes into streets, gutters, and storm drain systems, and ultimately, unfiltered and untreated, into creeks. This water can carry a variety of substances harmful to riparian ecosystems including fertilizers, pesticides, bacteria and viruses, heavy metals, organic chemicals, soil, and seeds of exotic plants.

Gardeners, by helping control the quality and quantity of water washing from the many gardens in a watershed, can play a vital role in the control of this non-point source of water pollution. The following suggestions may help:

· Use a flat shovel and a broom to remove soil and garden debris from walkways, driveways, patios, and gutters before rain. If washing with water is necessary, wash soil back into the garden, rather than into the gutter,

· Cover as much soil surface as possible with plants, mulch, or other materials suitable to help minimize erosion,

· Maintain irrigation systems to avoid leaks and gushers which can wash soil from the garden,

· Where possible, use permeable paving materials which allow water to move through them and into the soil,

· Loosen the surface of hard packed soil to increase water infiltration, and decrease surface runoff,

· Use plants with root systems sufficient to hold soil in place on embankments, and mulch to lessen the impact of water striking the soil surface. Irrigate in time periods of short duration to minimize runoff, and

· Carefully follow directions on pesticides and fertilizers to minimize excess application.

For gardens adjacent to creeks, bank stability, erosion control, habitat conservation, and invasive exotic plants are often issues related to placement of structures such as steps, fences, and retaining walls, and other modifications on or near creek banks. California Department of Fish and Game can provide relevant guidance and information.

The following websites also present information related to gardening practices and control of storm water runoff:

· http://wcrfre.ucdavis.edu

· http://wcrfrre.ucdavis.edu/research/water.asp

· http://www.asla.org/land/raindrain.html

Websites mentioned may be sites outside of the University of California domain. No endorsement is intended of products, services or information, nor is criticism implied of similar sites that are not mentioned.

University of California Cooperative Extension Master Gardener Volunteers can provide additional gardening information upon request. Call the San Luis Obispo office at 781-5939 on Mondays and Thursdays from 1 to 5 PM, the Arroyo Grande office at 473-7190 on Wednesdays from 9 AM to 1 PM, or the Paso Robles office at 237-3100 on Wednesdays from 9 AM to Noon.  The San Luis Obispo Master Gardener website is at http://groups.ucanr.org/slomg/. Questions can be e-mailed to mgsanluisobispo@ucdavis.edu.