Ocean Friendly Gardens, GAP
September 24 2012

Lawn Gone Without Chemicals

by Paul Herzog

After getting approval from the City of Santa Barbara for our plans to capture rainwater and our list of plants, we were ready to get to work on contouring the site and sheet mulching. Months prior, we were led through a Hands-On Workshop (HOW) on Site Evaluation by professionals with G3/The Green Gardens Group (read the blog post about it). The plans for the retrofit of the site were informed by the data collected during the Site Evaluation HOW. Days before the workday, the garden columnist for the weekly Santa Barbara Independent, Virginia Hayes, wrote a stellar piece on sheet mulching days and gave a shout out to the Surfrider event! (Click here for a "recipe" on how to create "soil lasagna," aka, sheet mulching, and we'll walk through the steps, below).

We kicked off the day with a refresher on the principles of OFG (applying CPR: Conservation, Permeability and Retention), followed by a welcoming from Santos Escobar, the City Parks Manager. (Prior to the workday, Santos and his crew had removed the turf grass and re-directed the raingutter downspout towards the landscape.) G3 professional, Pamela Berstler, then described the plan for the day: create a swale and sheet mulch.

Step 1: Hand removal of any remaining turf roots and trenching next to hardscape (walkways and sidewalk). More on the rationale of trenching in a moment.

Step 2: Ensure that the slope of the landscape is moving away from the building. The formula is easy: for every foot of earth, the slope must drop 1/4 inch. We used an ancient Australian water level called a bunyip to gauge how much soil needed to be excavated to ensure the flow of water through the swale. (Note: try as we might with pix axes to dig out the basin into which the downspout would pour, we struck a deal with the City to have their crew return in the coming weeks with an auger to dig out the area.)

Step 3: Apply compost tea. The site had been turf grass for years, with any applications of  chemicals and synthetic fertilizers reducing soil life. Just walking on the grass leads to compaction, reducing air and water flow through the soil. The tea, in combination with loosening the soil, builds soil life and aerates the soil (creates pathways for oxygen to flow).

Step 4: Sprinkle on humates. Humic acid is a main component of healthy soil, and is produced by biodegradation of dead organic matter. It is typically a mined material, and something we hope to see augmented with locally-produced, quality compost. Cathie Pare (at right), the City's Water Resource Specialist, lead the way. Check out the City's great online info for garden resources and rebate opportunities.

Step 5: Lay down bio-degradable turf barrier. We use a paper barrier, helping to block sunlight and prevent any remaining turf grass roots from photosynthesizing and re-growing. The paper is also a food source for the biology laid down in the compost tea. The paper is waterered as soon as it goes down. We dug down 8-10 inches along the hard surfaces and wrapped the paper snuggly against it to doubly ensure grass does not regrow. Meg West (standing at left, in plaid shirt and red shoes), landscape architect at Arcardia Studio and host of the local "Garden Wise" TV show, has at it. "Garden Wise" filmed the event for a future show.

Step 6: Spread out the mulch and water - The last layer of the lasagna was mulch and we laid it on about 3 inches thick. Watering the mulch helps with decomposition and keeping the soil and paper moist enough to support the soil life. Isla Vista Surfrider activist and OFG intern, Caitlyn Teague - at right - was covered in mulch dust at the end of the day (pictured at right dumping the wheelbarrow).

Since we have some time to finish up the grant-funded requirements, we planned to give the sheet mulch a chance to breakdown for six weeks before planting. We will return on Saturday, November 10 for a Planting and Irrigation Installation Workday. Some time after that, we will conduct a Lawn Patrol (neighborhood walk) that starts at this new Ocean Friendly Garden.

The Patrol will double as a Patrol training session, since we will need at least 12  leaders to head up Patrols monthly for the coming year as part of an agreement with the City to help maintain the site. (FYI, in the picture at left, the downspout runs down to the orange pylon, and will be extended into the garden near the westly boulders.)

As with the prior events, this workway was sponsored by the California Coastal Commission's Whale Tail License Plate Grant. In addition, we are grateful for the time and resources contributed by the City of Santa Barbara.