Finding a great strawberry

Kirk Larson knows that somewhere among the more than 25,000 plants he inspects every week, the next great strawberry may be waiting to be discovered.

A plant breeder for the University of California, he helps run a program that has produced some of the most delicious berries offered at local farmers markets — Gaviotas, Seascapes and Chandlers. And it has also succeeded in extending the fruit's season from the couple of months nature traditionally allotted to nearly all year-round.

Now the trick is finding a strawberry that will do both.

Though he doesn't know when this hero will turn up — maybe this year or maybe five or six years from now — he does know many of the things it will have to do. It will have to be a tough plant, resistant to the many pests that plague the crop. The fruit will be firm enough that you can ship it to New York and have it arrive looking just the same as the day it was picked in Oxnard.

The plant will pop out berries like a little fruit factory. And it will do so steadily over an entire yearlong growing cycle, regardless of the season or the weather. These days, having plants that produce during January and February's rains is not a bonus but a requirement.

The strawberries will be beautiful to look at, bright red and perfectly conical in shape. They will be huge, each one weighing about an ounce. And they will appear at the end of long stems, well free of the plant's leaves so they will be easy to pick.

The flavor? Well, the flavor should be good, too, but that's less crucial, from Larson's point of view. The history of strawberry breeding is littered with great-tasting berries that are no longer popular. The most recent example is the Chandler.

"The fruit looked great and tasted good, but if you shipped it to New York, when the buyer opened the box, the fruit was all leaking out the bottom — that's an automatic rejection," Larson says.

"You've paid all that money to grow the fruit, pack it and ship it, and it's a total loss. That only has to happen a couple of times before you get real tired of it."

That may sound hard-nosed, but it is this philosophy that since World War II has transformed what was once a tender icon of spring into one of the marvels of modern industrial agriculture. Since 1950, California strawberry growers have increased their production more than twentyfold, from 81 million to about 1.67 billion pounds.

A growth industry

Last year, strawberries earned more than $1 billion and were the fourth most profitable fruit or vegetable grown in California, behind only grapes, lettuce and almonds. The state now produces more than 85% of all the strawberries grown in this country and more than 20% of all the strawberries grown in the world.

At the root of this transformation have been the breeding program's strawberry breeders. Larson, working out of the South Coast Research and Extension Center at Irvine, and his partner Doug Shaw, who operates out of Davis, are the newest generation.

The two are split because growers in different areas of the state have different demands, both aimed at cashing in on the lucrative off-season market. There is far more money to be made selling strawberries when nobody else has them than trying to peddle them when the stores are glutted. The same flat of strawberries that sells for $6 to $8 in June can fetch a farmer $30 and more in December or January.

In Southern California, farmers prize "short-day" varieties that will ripen early. In the north, they prefer "day neutral" berries that will produce well past the traditional end of the season.

Put together, the UC varieties account for almost two-thirds of all the berries grown in the state. Overseas, their share is even higher. Roughly 90% of the strawberries grown in Spain, the second-largest producer, come from University of California varieties, and these same varieties are similarly influential in strawberry fields from Mexico to Morocco.

In addition to the University of California program — which is partially funded by growers through the California Strawberry Commission — there are two major private strawberry breeding programs in the state, managed by shippers Driscoll's Inc. and Well-Pict Inc. These proprietary varieties make up about one-third of the California harvest.

If ever there was a fruit that seemed designed to frustrate industrial agriculture, it is the strawberry. From the tips of its berries to the ends of its roots, it is the essence of vulnerability.

Unlike most fruits, strawberries wear their seeds on the outside of their flesh rather than the inside; there is neither skin nor peel to protect the sweet meat from the predations of climate and pest. This fragility is only amplified after the fruit has been picked, as the teeniest nick or cut can become an open doorway for the fungi that lead to rapid decay.

If anything, the roots are even more vulnerable than the fruit. They lack any corky bark or peel that would protect their simple tissue from soil-borne pests. As a result, an established field of strawberries is little more than a well-advertised, all-you-can-eat buffet for almost any bug around. Verticillium wilt, anthracnose crown rot and two-spotted spider mites are just a few of the most obnoxious.

Because of all of this, strawberries are extremely expensive to produce. A recent study by the California Strawberry Commission, a growers' organization, predicted costs of more than $30,000 an acre to grow the fruit, harvest it and ship it (for comparison, lettuce is less than $10,000). This leaves farmers scrambling for any advantage to make their investment pay off.

That's where Larson and Shaw come in. Their job is to find the one plant in a million — almost literally — that can give farmers an edge. It might be a plant that pops out more fruit or produces higher quality berries (even with the best of the newest varieties, farmers discard up to 20% of fruit as too small, poorly colored or misshapen).

Or it might be a plant that produces exceptionally well either early or late in the season, when the prices are highest.

Low-tech fruition

The search for this perfect plant begins not with any kind of modern genetic technology, but old-fashioned birds-and-bees pollination. Larson selects a pollen-bearing male flower from a plant with desirable traits and rubs it around the center of a female flower from another selected plant.

When that fruit ripens, the seeds will be collected and planted (technically, these seeds are actually achenes; they are tiny dried fruits themselves, each one containing a seed).

Each plant will be a fraternal twin of the others from the same berry, sharing many traits, though slightly different. The plants that seem most promising will be selected and planted outdoors in fields the next year.

In the field, the new plants are numbered and grouped according to their parentage. If you look closely enough you can see the resemblances and also the differences. This plant may have large, perfectly formed fruit while its sister right next to it bears strawberries that are similarly sized but more frequently misshapen.

Larson walks the fields nearly every day for the 28 weeks that make up the heart of the typical Southern California strawberry growing season, which runs from mid-November into June.

In a hand-held Allegro CX computer loaded with a spreadsheet, he scores each plant on a variety of criteria. He counts the fruit and grades it for size, shape and color. He grades the plant's "architecture" — how the leaves and fruit are presented — and several other factors.

"I'm looking for the drop-dead gorgeous strawberry poster child," he says.

This early on, he doesn't pay much attention to flavor. It is just too subjective and it changes from week to week, depending on weather, variety and the individual plant. Of course, there are more mundane reasons for not tasting every plant every week as well. "I do love strawberries, but I'd have to be eating thousands a day to make it meaningful," he says. "I try to take a bite whenever I can from plants I like, at least until I start feeling bloated."

At the end of the year, he'll run the spreadsheet and analyze each plant for productivity and value. Of the 13,000 or so in the initial selection, he'll pick the best to go on to the next year. This time, he'll cut shoots from the strawberry and plant those (seeds vary genetically, while propagating from plant division ensures identical clones).

The process will repeat with further winnowing each year until one plant has proved its worth to become a variety, which means that it has been patented and licensed and that growers will have to pay a small royalty to plant it. (Once the university has covered its costs, it shares the royalties with Larson and Shaw, following a complicated formula.)

This season, in addition to the new trials, there are 487 strains from last year's first selection that made the cut. There are also 160 from the year before that, as well as a few from 2002, 2001 and 2000.

One plant survived from 1999, but Larson says this year will be its last. "I had pretty high hopes for that one to become a variety, but it just doesn't look like it's going to make it."

Even after a variety has been selected, it still has to be tried out in test plots maintained by farmers at various locations throughout the state.

All told, it takes, at the bare minimum, six years to find a plant that is worthy of becoming a named variety. It frequently takes even longer. The Chandler berry, which was introduced in 1983, took seven years for Larson and Shaw's predecessors Victor Voth and Royce Bringhurst to develop. And it took Voth a decade to select Chandler's successor, the Camarosa.

"Growers are impatient; everybody always wants something new," Larson says. "We just released the Ventana a couple of years ago and already people are asking me when I'll have a replacement for it.

"I'm telling you, it's not easy to do, at least partly because we've set the bar so high. If you wanted to replace the Chandler right now, I've got hundreds of plants that would be better. Replacing the Camarosa or the Ventana is not so easy.

"In the 20 years since the Chandler was introduced we've pretty much doubled the yield and probably tripled the shelf life of strawberries," says Larson. "We've added at least another month to the season if not six weeks. If this were a new biotech start-up, everyone would be all over us. But because it's strawberries and we're just sticking pollen from one plant onto another, something that's been done for thousands of years, nobody thinks much about it."

Varieties' ups and downs

Once a variety is chosen and endorsed by the growers, it can spread quickly. Within just a couple of years of its introduction in 1993, the Camarosa accounted for all but a tiny fraction of the strawberry acreage in Southern California and a huge chunk in the northern part of the state as well.

Now the Camarosa is well on the wane, down to less than 20% of the state's harvest. Its successor, the Ventana, was first planted widely in 2002 and now accounts for almost 15%.

Each succeeding variety offers improvements on the previous one, but also has flaws of its own. "No variety is perfect; there are always trade-offs," says Larson. "There are 100 criteria we have to assess, and there is no perfect variety that has all of them and there probably never will be."

The Chandler berry had great flavor, but was too soft to ship very well. It also tended to bear fruit in spurts and droughts, which was hard on pickers.

The Camarosa is exceptionally firm and ships very well. It also has much larger fruit, is a heavy bearer and is much easier to harvest, even though the flavor isn't quite as good as Chandler — particularly when it is picked too early.

The Ventana bears a lot of fruit very early, the fruit tends to have better shape, texture and color than the Camarosa and is at least its equal in flavor.

Along with the successes have been varieties that didn't work out quite as well as hoped — from the large commercial growers' point of view, anyway.

The Gaviota, for example, introduced in 1997, has excellent flavor but does not bear heavily enough and the fruit lacks shelf life. It is doing well in the farmers market niche, where growers can get a bonus price for delicious fruit without worrying about it having to survive a truck trip to Manhattan. Seascapes, introduced way back in 1991 (practically ancient by strawberry standards), have survived for the same reason. The Camino Real, introduced in 2001, is a heavy producer with good fruit quality, but it doesn't produce well in either the very early or very late season and so has remained a minor player.

The Diamante, also introduced in 1997, has good flavor but is very, very firm and it lacks internal color, which limits its use in processing. It still represents more than 20% of the state's crop, but growers will probably begin to replace it when the new Albion variety hits the big-time next season.

"That's going to knock people's socks off with flavor," Larson says.