Healthy soil and sustainable growing

[yarrow@sfo.com]

Title: perennial vegetables

I've been reading the new book on perennial vegetables mentioned in the article below and am a bit disappointed that it doesn't include more detailed information on the plants I am growing -- yacon, walking kale (tree collard), lovage, cardoon. Also, most of the plants are subtropical. But it's interesting to read about the possibilities. Back to the seed catalogues....

http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2007/11/24/HOFKT0647.DTL

Perennial crops: The garden that keeps giving

Deborah K. Rich, Special to The Chronicle

Saturday, November 24, 2007

T here are a lot of reasons to grow perennial vegetables.

For starters, they require less work than annual vegetables. Second, they are already commercially available. Finally, perennial vegetables bring new flavors and textures to the home garden, ranging from the lemony tartness of French sorrel to the creaminess of baked oca, an Andean root crop.

"That oca is incredible; people specifically covet oca," said Brock Dolman of the Occidental Arts and Ecology Center in Occidental. "You roast oca with potatoes and carrots and toss in some olive oil and a little salt and garlic and crisp it up and you've got something wonderful. Oca is just one of the great foods. It's not clear to any of us why that plant has not made its way into the modern cuisine, because it's productive and it's amazing."

Dolman wears many hats at the center, including as manager of the center's biodiversity collection, orchards and 70 acres of wildlands.

The land the center occupies has a long history of perennial food crops. Acorns and hazelnuts were staples of the Pomo Indians who lived there for generations. Later, Italian homesteaders brought their pears, olives and grapes.

In 1974, the Farallones Institute purchased the land. The early visits by Bill Mollison, a founder of the permaculture movement, and by Robert Kourik and Rosalind Creasy, both authors of books on edible landscaping, prompted the incorporation of perennial vegetables into the Farallones' bio-intensive gardening.

"I was able to just show up here in 1994 when the OAEC bought the farm, and there was this amazing scene already under way, and to inherit it, and then to expand it," Dolman said.

Today, under the care of longtime garden manager Doug Gosling, the center gardens include a wide array of perennial food plants, ranging from other Andean root crops like mashua and yacón to cardoon, cape gooseberries, tree collards, pepinos, nettles and lovage. The perennial vegetables are standard fare for residents and visitors to the center, and perennial vegetable starts are available to the public in its annual plant sales.

Once established, they give forth their bounty year after year while requiring little more than watering and a new layer of compost.

For Eric Toensmeier, manager of an urban farm project for Nuestras Raíces in Holyoke, Mass., and author of "Perennial Vegetables" (Chelsea Green Publishing, 2007), that's one of the main reasons to plant them.

"They're less work," he said.

"I have plants in my garden here that I started from seed seven summers ago, and I've done almost nothing for them since. I mulch them and give them some compost and harvest. In your perennial garden, you work so much less than your annual garden."

In the case of perennials, what's good for the gardener is also good for the soil. Generally, less tillage means less disruption of the soil food web that recycles and mobilizes soil nutrients. Because perennial roots and plant crowns remain in place even throughout the winter, they help protect the soil from wind and water erosion. The relatively permanent roots also provide a nearly continuous supply of carbon-rich nutrients to the soil food web in the form of its exudates (compounds that roots secrete to deter pathogenic micro-organisms and mobilize nutrients) and sloughed-off cells.

Though the year-in, year-out work is less than with annuals, a little extra care when preparing the soil to receive perennials goes a long way. Remember, with any luck, the ground won't be laid bare for easy tilling again for five to 10 or more years, depending upon the vegetable and how happy it is in its location.

Building in good soil fertility is especially important in beds designated for perennial vegetables.

"Unlike a perennial flower bed, you're going to be harvesting material out of there," Toensmeier said. Gardeners may want to have a soil test done to identify any nutrient deficiencies, and to add specific nutrient amendments with compost.

Any perennial weeds should be removed thoroughly; they'll be harder to grub out once the vegetables are established. Adding thick layers of mulch after planting will help keep them down.

Planting is also the time to install drip irrigation. It saves water, aids in weed control and helps to avoid the fungi and leaf blights that can be brought on by overhead watering.

Plant placement is as important for perennial vegetables as it is for perennial ornamentals. Many perennial vegetables grow much larger than the typical annual vegetables. Artichokes, one of our most celebrated perennials, occupy a 3- to 5-foot-diameter circle when fully grown. Chayote vines can meander for 30 to 100 feet, with one plant producing as many as 100 fruits a year, and the perennial hyacinth bean likes to climb up pergolas and 18-foot trellises.

Some, like nettles, which spread by both rhizome and seed, can colonize large areas - a plus only if well placed.

"Nettles can grow in a riparian corridor, and we're actively planting those in the appropriate wet places around here to get them to grow like crazy so that we have a lot of them. When you're really trying to eat them as a mainstay vegetable, you need plenty of plants," said Dolman of the center. " 'Right plant in the right place' is always the mantra. And if a plant is out of control, it's not the fault of the plant, it's the fault of the planter."

Perennial vegetables may be easiest to handle in a separate bed or installed as a border along one side of a bed of annual vegetables. "If you manage your garden for annuals and till every year, you're going to need to put your perennials off to one side so that you're not always having to work around them," Toensmeier said.

Perennial vegetables range from greens and crunchy stalks to beans, melons, tubers and tomato-like fruits. Toensmeier cautions that perennials can often have stronger, "somewhat foreign" tastes. Okinawan spinach leaves, for example, are "almost piney" in flavor, best served as an accent flavor in salads rather than as the main green, and lovage has an intense celery flavor.

On the other hand, cooked nettles reportedly taste like nutty spinach, and oca is sweet and tart like good star fruit when raw and tastes like potatoes with the sour cream already added when baked. Yacón is a tuber that is enjoyed like a fruit for its sweet apple taste and crispness.

"Many people have grown these for a long time," Dolman said. "I think their apparent strangeness is more an artifact of our industrial food system. I think it's harder to mechanize some of these perennials. It's one thing to mechanize a tomato, it's going to be harder to mechanize a tree collard."

Seed and plant sources. F8

General seed and plant sources
-- Educational Concerns for Hunger Organization (ECHO): 17391 Durrance Road, North Fort Myers, Fla. (239) 543-3246, www.echonet.org .

Seeds of tropical perennial vegetables
-- Evergreen Y.H. Enterprises: P.O. Box 17538, Anaheim. (714) 637-5769, www.evergreenseeds.com .

Seeds of Asian perennial vegetables
-- J.L. Hudson: Star Route 2, Box 337, La Honda. www.jlhudsonseeds.net .

Rare seeds from every continent
-- Occidental Arts and Ecology Center: Thrice-yearly on-site sales only. 15290 Coleman Valley Road, Occidental. (707) 874-1557, www.oaec.org .

Yacón
-- Seeds of Change: P.O. Box 152, Spicer, Minn. (888) 762-7333, www.seedsofchange.com .
-- Nichols Garden Nursery: 1190 Old Salem Road N.E., Albany, Ore. (800) 422-3985, www.nicholsgardennursery.com .

Mashua
-- McClure & Zimmerman: Spring catalog only. 108 W. Winnebago St., P.O. Box 368, Friesland, Wis. (800) 883-6998, www.mzbulb.com .
-- Goodwin Creek Gardens: P.O. Box 83, Williams, Ore. (800) 846-7359, www.goodwincreekgardens.com .

Oca
-- Goodwin Creek Gardens (information above)
-- Nichols Garden Nursery (information above)

Organizing, education center and organic farm
-- The Land Institute: 2440 E. Water Well Road, Salina, Kan. (785) 823-5376, www.landinstitute.org .

Developing perennial grains
-- "Perennial Vegetables: From Artichoke to 'Zuiki' Taro: A Gardener's Guide to Over 100 Delicious, Easy-to-Grow Edibles," by Eric Toensmeier (Chelsea Green Publishing Co., 2007).
-- "Lost Crops of the Incas: Little Known Plants of the Andes With Promise for Worldwide Cultivation," by the National Research Council (Books for Business, 2005).

E-mail Deborah Rich at home@sfchronicle.com.

This article appeared on page F - 1 of the San Francisco Chronicle


http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2007/11/24/HOFKT0IEM.DTL

10 perennial veggies to grow

Deborah K. Rich

Saturday, November 24, 2007

California, especially near the coast, is blessed with a climate suitable for many perennial vegetables. Many gardeners are already familiar with artichokes, rhubarb and asparagus, but there are dozens more to choose from. Here are some top recommendations:

Cardoon: Though it looks like an artichoke plant, cardoon differs from its more familiar cousin in that it is primarily the midribs of the leaves that are eaten, rather than its flower buds.

Traditionally, cardoon leaves are blanched by being bent over and buried under the soil, though they don't have to be. Sliced and cooked cardoon midribs taste like a plateful of artichoke hearts. Only one or two plants are needed to produce a pile of midribs.

French sorrel: The leaves of French sorrel add a lemony tang to soups and salads. In mild climates, the leaves are edible year-round, especially on varieties that never flower. Cutting back the flower stalk will ensure a long supply of tender greens.

Jerusalem artichoke: (a.k.a. sunchokes) The Jerusalem artichoke grows 4 to 12 feet tall and produces small flowers resembling wild sunflowers. Its tubers are crisp, nutty and sweet, and can be eaten raw, baked, boiled in soups or mashed along with potatoes. When harvesting, simply leave some tubers in the ground to produce the following year's crop. (If the tubers are not thinned by harvesting, Jerusalem artichokes can spread rapidly.) Inulin, a storage starch in Jerusalem artichokes, can cause gas, especially for those unaccustomed to eating them. Inulin is believed to improve the body's ability to absorb calcium, and to increase beneficial microbes in the digestive tract.

Lovage: Lovage is a large celery-like perennial that grows up to 6 feet tall. Its flavor is very intense. The young leaves and stems lend themselves well to soups (later growth is too strong-tasting to eat), and the seeds can be used for flavoring. In cold areas lovage, like French sorrel, is often one of the first greens to emerge.

Mashua: An Andean root crop, mashua is a relative of the nasturtium. Mashua is a vigorously growing vine; give it a trellis to climb. Its red and yellow blooms are favorites of hummingbirds. After the frost kills the aboveground part of the plant, it's time to dig out the long, white, fingerlike tubers, which can be baked, roasted or put in a soup. Mashua has a unique peppery flavor. Plants produce dozens of tubers; the best can be saved and replanted like potatoes, but since it is hard to find all the tubers, mashua, like the Jerusalem artichoke, often becomes a "true" perennial, regrowing from unharvested tubers.

Nettle: Be warned that nettles are covered with stinging hairs; wear gloves and use scissors to harvest the leaves and fresh shoots. A quick cooking will take away the sting, and the cooked tender leaves and shoots taste like spinach. Steam, boil or use like spinach. Nettles are high in protein, vitamins A and C, iron, magnesium, calcium, potassium and fiber. Nettles spread by both rhizome and seed, forming a dense patch.

Oca: Another Andean root crop grown similar to potatoes. The tubers are harvested at the end of the growing season. Yields will be higher if tubers are dug and replanted. Oca not only tastes delicious both raw and cooked, but it also produces high yields in small spaces. With leaves that look like clover, oca grows in clumps about 1 foot high. The California coast is one of the few locations suitable to grow oca in North America because oca does not begin to form tubers until late in the summer, and then still needs at least two to three frost-free months to ripen them fully.

Pepino dulce: The pepino plant actually produces a fruit rather than a vegetable, although unripe fruits are sliced and eaten like cucumbers. When ripe, pepino fruits are about the size of a large tomato with beautiful yellow skin bearing purple, gray or green stripes. The flesh tastes similar to cantaloupe. Like the tomato, the pepino benefits from staking. A frost below 28 degrees will kill the pepino to the ground, but it will resprout in the spring if the roots weren't damaged.

Tree collards: Tree collards produce a kale-like brassica leaf year-round in cooler climates. The leaves are good steamed, braised and in soups, stews and casseroles. Tree collards may not be as productive where summers are hot. Tree collards can be left to spread out along the ground, eventually occupying a large area with a mini-thicket 3 feet tall or so. Alternatively, where space is tight, tree collards can be trellised.

Yacón: An aster, and yet another Andean root crop, yacón produces small, football-like tubers that are mostly eaten raw, similar to a jicama. Yacón is crunchy, juicy and a bit sweet, lending itself to crudites. Yacón grows into a lush 6-foot-tall shrub. The large storage tubers form below a crown of smaller tubers, which are broken apart and replanted at harvest. Like Jerusalem artichokes, yacón contains inulin.

This article appeared on page F - 9 of the San Francisco Chronicle

http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2007/11/24/HOFKT0670.DTL

The potential for growing food from perennial crops

Deborah K. Rich, Special to The Chronicle

Saturday, November 24, 2007

Perennial crops have great potential. Yet they hardly figure in the world's calorie consumption.

The world's major grains, food legumes and oilseeds - including all of its wheat, rice, corn, barley, soybeans, cottonseed and dry beans - are annuals. These crops covered 80 percent of harvested cropland in 2004.

A food system based upon plants that start each growing season anew from seeds is inherently risky.

Farmers' efforts to reduce the risk often degrade soil and water and accelerate the buildup of greenhouse gasses.

Many crop seeds won't germinate if the soil is too hot, cold, wet, dry, crowded or full of clods. With plow and disc, farmers clear the soil of weeds and debris and slice it into a fine crumb. If it's a spring planting, they wait for the soil to warm. For a fall planting, they wait for it to cool. In the arid West, farmers "irrigate up" before planting; in the changeable Midwest, they squeeze in planting between thunderstorms.

Weeds enjoy the farmers' carefully prepared seedbed just as much as crops. Farmers cultivate, spray herbicides or hoe to keep weeds under control while their crops get established.

There is a beginning for perennials as well, complete with seedbed and coddling of seedlings. But the initial soil disturbance and fieldwork pay off for several years.

Alfalfa, a legume grown for animal feed, often produces for five years or more. Without the need to disc and plant each year, tractor use is less, fuel use declines and the soil suffers less degradation.

Agroecologist Jerry Glover of the Land Institute demonstrates the power of perennial plants.

Arms outstretched, he holds up a clump of annual wheat in one hand and a handful of wild perennial wheatgrass in the other. While the slender roots hanging from the clump of wheat fall barely to Glover's elbow, the boisterous tangle of wheatgrass roots tumbles down to his feet.

"You can visualize roots as a series of safety nets for the soil," he says. "Safety nets not only with depth, but extending over time."

Within the first year of planting, the roots of perennial crops leave little room for weeds. Glover thinks that a reduction in herbicide costs of four to 8 1/2 times is a conservative estimate.

"I have 5-year-old wheatgrass plots that are weed-free and have never had herbicides," says Glover. That saves money, reduces tractor passes and benefits environmental health.

Perennial crops extend the growing season, partly by already being in the ground as winter is ending. In states such as Kansas, where the Land Institute is located, it isn't unusual for only half the days in a month to be suitable for planting.

Perennials start growing first. "Root activity can take place at much cooler temperatures than seeds can germinate," he said.

They also stretch out the growing season. In late September, Glover's wheatgrass had already regrown 4 to 6 inches after being harvested in August while he waits to reseed his wheat field.

"Our annual winter wheat won't do well at all in July or August," says Glover. "It doesn't even matter if we can get the seed to germinate; the winter wheat just can't grow in those temperatures, and the surface of the soil is too dry for the seedlings. Yet our perennial wheatgrass, because its roots are deep down, is able to reach where the soil is more buffered against extremes in temperature and moisture."

Reaching deep into the soil year-round, perennial roots make more efficient use of nitrogen inputs, half of which can leach out of the root zone before plants can make use of it.

"Nitrogen in the soil typically moves with water," says Glover. "You don't want to have water flowing through the system unused. Picture Iowa in April or May. There's no crop growing because it's too cold, but yet they're getting a lot of rainfall."

Not only are nitrate losses a waste of an expensive input - the price of nitrogen is on the rise along with the price of oil - nitrates draining into waterways fuel the spread of coastal dead zones.

Spring and summer nitrate flows out the mouth of the Mississippi River cause massive algae blooms that rob the water of oxygen and create dead zones in the Gulf of Mexico.

The perennial web of roots holds onto more than nitrogen.

The roots anchor the soil and reduce erosion. A study begun in 1888 at the University of Missouri measured the depth of topsoil remaining after 100 years of continuous farming.

Topsoil under plots of perennial timothy grass (a crop cut for hay) was more than two times deeper than the topsoil remaining under annual corn, and almost 1 1/2 times deeper than the topsoil remaining under a six-year rotation of corn, oats, wheat, clover and timothy grass.

With the world's population growing, agriculture must anchor all the soil it can as ever more marginal land is pushed into production.

"We get away with a lot here in North America because our soils are so rich, fertile and deep. The thinner or more poor your soils are, the more you need perennials there to safeguard them," says Glover.

Conversion to perennials cannot happen overnight.

The Land Institute began its perennial breeding programs in 2000. Today it has four breeders and total funding of approximately $2 million.

Glover estimates that the institute is probably at least 25 years out from having a high-yielding perennial substitute for a major grain. The world may come asking for seed sooner.

"How far out we are from having a product partly depends on expectations," says Glover. "Our wheatgrass, for example, right now out-yields some of the world's minor annual crops, such as Ethiopian teff, in a good year. Also, for some of the non-food-crop oilseeds, you don't have all the taste and handling requirements that you have for wheat. You want a very consistent bread, but for oil you're more flexible. And how far we are from a commercially viable crop will partly depend upon world resources."

This article appeared on page F - 9 of the San Francisco Chronicle