Raise a bed of great vegetables

Sunset, March, 1996 by Jim McCausland

Virtuoso gardener Peter Chan shares his secrets for growing crops in raised beds

When our friend Peter Chan told us he was going to create a new vegetable garden in Northern California, we were eager to watch. Chan is one of the West's best vegetable gardeners, and his gardens are as highly productive as they are beautiful.

We first met him about 15 years ago, when he won a Sunset garden contest. He was living in Portland and would soon publish the classic text on Chinese raised-bed vegetable gardening (Better Vegetable Gardens the Chinese Way, now out of print). A practical man with an engaging manner, he went on the horticultural lecture circuit, where he's had a major impact on the way Americans garden.

Then, a year ago, Chan moved to the San Francisco Peninsula, where he planned a new garden in his small backyard. He invited us to observe as the garden took shape, and after seeing it flourish, we're happy to report that his techniques work as well in California as they did in Oregon. And they can work in your garden, too.

RAISING THE BEDS

Chart, who once taught at an agricultural college in China, favors raised beds because they get maximum production from minimum space. Soil in such beds warms earlier in spring, drains well, and never gets trod on, so it remains loose and easy for roots, air, and water to penetrate.

In a way, his job was made easier by the native heavy clay soil: it was so bad he didn't even consider planting in it or amending it. Instead, he built the 3 1/2- by 14-foot raised beds. Each is made from recycled redwood 2-by-10s nailed to comer posts of 10-inch 4-by-4s.

The width of the beds was determined by Chan's reach; from the path, he can easily weed the center of each bed (if you have longer arms, make your beds commensurately wider). The length of the beds was determined by the space available, but Chan advises against anything longer than 20 feet.

The beds are oriented roughly east-west for maximum sun exposure for all plants. Between the beds are 18-inch-wide dirt paths packed down with blows from the back of a spade. In winter, he covers them with straw or bark dust; gravel, brick, or concrete would work as well.

For climbing crops - peas, beans, and cucumbers - he adds an A-frame trellis system (pictured at right) made from galvanized plumbing pipes that were drilled, sprayed with zinc, and bolted together. The A-frames support wire or twine for the vines to climb.

PLANTING MIX IS A SPECIAL BLEND

Before filling the beds with planting mix, Chan dusts the bottom of each with lime, then covers that with an inch of mixed chicken and steer manure or homemade compost. A planting mix composed of 50 percent aged redwood compost, 40 percent top-soil, and 10 percent sand tops off the beds.

The fertilizer is never blended into the planting mix; it stays put on the bottom of each bed to encourage plant roots to grow deep. Keeping the top inch of soil relatively infertile also discourages weed seedlings from getting a fast start.

NOURISHING PLANTS

In China, Chan grew everything from seed. These days, he grows most of his first crop of vegetables from nursery seedlings he buys in mid-March. He favors bok choy and other Chinese vegetables, cabbage, lettuce, spinach, tomatoes, peppers, eggplant, and bitter melon. He grows beans and Chinese pea pods from seed.

After the first nursery-grown seedlings are in the ground, he starts later crops from seed when warmer air and soil encourage germination. To give seedlings a push, he mixes 1 tablespoon of fish emulsion per gallon of water, then pours it along the sides of growing plants twice each week. He continues this feeding method, called side dressing, all season for leafy vegetables, but fruit-bearing vegetables (like beans, peas, cucumbers, melons, peppers, squash, and tomatoes) get fed only until they flower; then they're on their own.

He also gives fish emulsion to root vegetables like potatoes and radishes through the season, adding a little high-potassium fertilizer if a soil test tells him it's needed.

Watering is done early in the day. Chan irrigates with a watering wand on a hose, dousing the tops of leaf and root crops completely, but keeping water off the fruiting vegetables (he doesn't want to rinse any pollen off the flowers).

ROTATING CROPS

Because his raised beds are used for long-term food production, Chan fights soil-borne diseases by rotating crops. If he plants cabbage family members in a bed this year, he'll put a completely different crop (tomatoes, for example) in that bed next year. Ideally, a bed never grows the same crop more than once in four or five years.

After a crop comes out, Chan freshens the beds by shoveling soil out of the center third of each bed and piling it on the ends. Then he sprinkles lime in the dug-out area, adds another inch of manure or homemade compost, and brings the old soil back. He repeats the process for the ends of the beds, then waters and lets the soil settle before replanting.