A city farmer faces the challenges of urban gardening

In Los Angeles, an urban gardener with dreams of farming in the city found that her soil was too polluted with lead and zinc to grow vegetables in the ground. But she didn't let that stop her.

Because of the toxins in her urban soil, Susan Carpenter had to build raised beds to contain her plantings.

Los Angeles Times photo by Ken Hively.

November 18, 2009

There are certain phrases I never expected to utter in my lifetime. Things like, "Excuse me if I don't shake your hand. Mine's covered in horse urine." Or, to my son, "When you're finished with dinner, clear your plate and feed the scraps to the worms."

Yet those are exactly the sorts of things I've found myself saying in the months I've been an urban farmer.

A year ago, I didn't have a vegetable garden. I had a couple of lemon trees, but I'd given up on potted plants, having killed every rooted thing I'd attempted to nurture on my back deck. I didn't just have a black thumb. I had a black hand.

But last year I began to think that my little postage stamp of a property could do more than just look pretty. Ideally, it could be put to work. I just needed to learn how.

It's kind of shocking how little I know about plants and soil, given that my mom grew up on a farm and one of my uncles still works major acreage growing corn. In a single generation, the information chain that had passed through my family for centuries was broken.

Like many others in Los Angeles, I bought my food at the supermarket, and my landscape was professionally designed and maintained. I rarely, if ever, touched dirt.

I needed an expert who specialized in small-scale city farming. That person was Tara Kolla. She has been running Silver Lake Farms from her double lot in one of the city's hip neighborhoods since 2004.

Ms. Kolla teaches gardening workshops and is available for one-on-one property consultations. I hired her last September to do both, and she dug into my project with gusto.

She pawed into my soil with bare hands, scooping out samples to send to a lab so she could see what we were working with. A couple days later, we found out. It was poison, basically. Like a lot of dirt in this city, mine was a victim of car culture, containing high, unhealthful levels of zinc (from brake dust) and lead (from the days of leaded gasoline).

If was going to farm my property, I had two options: build raised beds or remediate the soil by growing a cover crop that would suck up the metals. I chose option No. 2.

At that time, my property was a thriving xeriscaped paradise, which meant I needed to get rid of all my plants. The idea of throwing them away sickened me, so I threw a dig party, inviting my friends to come over with their shovels and take away the flax, hibiscus, and any other plants they wanted.

That cleared about two-thirds of what needed to be removed. The rest required professionals.

At Kolla's suggestion, I planned to grow vegetables in my front yard, because that's where I had the right amount of sunlight. The side of my house, with its morning light, would be transformed into a berry patch. My backyard: an orchard of citrus and stone fruit trees, as well as flowers.

For the front and side yards, Kolla suggested something that seriously upset my street's landscape status quo. The scraggly mess of sweet peas, hairy vetch, and beans looked like weeds. But I let them grow. For months. I pulled them out in May so I could plant my first summer crop with the seedlings I'd successfully grown from scratch, thanks to Kolla's seedling and soil workshops.

Before planting, I sent another round of soil samples to the lab to see if the cover crop had helped.

It had, but not nearly as much as needed. The lead level had dropped by half and the zinc by about 40 percent, but according to Garn Wallace, the scientist who was doing my soil testing, I would need to do the same cover crop regimen for 10 years before I could eat vegetables that grew in that dirt. (Berries and fruits would be fine, he said, because their roots drill down to better soil, and because most soil toxins end up in stems and leaves, not the fruit.)

The sobering lab report meant I had to replace the soil in my front yard or build raised beds. My yard isn't big -- just 70 square feet -- so I decided to dig. I needed to excavate 2 feet deep. That's as far down in the topsoil as the airborne toxins from cars tend to go and as deep as the roots of most vegetables tend to extend.

But I underestimated exactly how much dirt that was. Hiring three day laborers for two days had gotten rid of only the top 6 inches. I had spent $600 and hadn't even purchased my replacement dirt.

So I bailed on my original plan and went with raised beds, which, like everything else, were problematic, time-consuming, and expensive.

I needed to use untreated wood so that chemicals wouldn't leach into the soil, and I wanted a hearty wood. That meant redwood, which, in the 14-foot lengths I needed, cost more than I had spent on grocery-store vegetables for, oh, at least three years. But at this point I was deep into the project and determined to see it through.

A friend and I built the boxes, I bought a load of dirt from a nursery and a load of horse manure, and I was in business. I repurposed my sprinklers to drip line and planted my seedlings in the boxes.

On to the backyard. After putting in a few citrus trees, I realized I was seriously challenged in the design department. What I'd done looked OK, but I wanted beautiful. I reached out to a landscape designer whose work I'd admired for years and who is willing to advise for an hourly design fee of $90 with a 10-hour minimum.

I appreciated her eye for Dr. Seuss-ish flora and her use of California natives. In designing my backyard, she used a mix of exotic flowers and an artful display of edibles, such as blueberries and grapes -- all of it to be fed from a rainwater catchment scheme she designed for my roof.

Once it actually rains in Los Angeles, the system will channel the water into infiltration pits and keep it on my property to deeply hydrate the soil.

It's been one year since I began my edible-garden adventure. For the most part, I'm pleased. I love watching my 6-year-old roll down the driveway on a scooter and stop for a strawberry. I love being able to chop fruits and vegetables without having to peel off a sticker. I love knowing that what I'm growing and feeding my family is healthful.

Although my backyard has yet to bear fruit and flowers, I did one last test to see if the vegetables from my front yard were clear of toxins.

I picked a bean, a tomato, and a passionfruit from my front yard and a leaf of chard from a deck-top planter box I had built and filled with bagged soil. The bean, tomato and passion fruit proved perfectly edible. It was the chard growing in the bagged soil that came back high in lead. That made me realize two things:

1) We're living in an incredibly polluted society.

2) As difficult and expensive as urban farming is to get started, and as labor-intensive as it is to maintain, it feels good to be closer to the land. The fresh veggies are only part of the benefit.

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