Authors: Barry Estabrook
Tags: #Cooking, #Essays & Narratives, #Specific Ingredients, #Fruit, #General
So he and his associates must still pack their collection equipment and head back out into the field. Their latest trip to northern
Peru in 2009 illustrated the severity of the
conservation challenge. When Rick and others had visited the area decades earlier, they made detailed records of where they observed native populations. Chetelat intended to return to the same sites to reexamine those populations.
Since the mid 1990s, intensive
sugarcane agriculture has come to low-lying valleys north of Lima, vast
monoculture fields carpeting the valley floors from one mountain range to the other. Chetelat talked to farm supervisors and laborers who formerly nibbled the ubiquitous little tomatoes as snacks, as we might pick a few wild blackberries in the fencerow beside a pasture. They told him that when the sugarcane came, accompanied by the usual herbicides and other agricultural chemicals, the tomatoes disappeared.
Everywhere Chetelat went, the story was the same. It was only when his group ventured higher into the mountain valleys, above one thousand meters, where conditions were too rough and available
spaces too small for sugar estates, that they began to find wild tomatoes growing in rocky areas and out of cracks in fieldstone walls. “That area is the center of diversity for one of the immediate ancestors of the cultivated tomato,” he said. “And now most of those populations are gone.”
In an effort to evaluate the situation more thoroughly, Chetelat is hoping to return to the region sometime in the next few years. Despite the modern advances in genetics and DNA mapping, this expedition will be more in the spirit of early plant collectors like Dr. Rick, the center’s founder. His goal is to secure funding from the
National Science Foundation to work closely with a team of Peruvian graduate students. Like the old-time botanists, they are going to scour the landscape and count individual plants at differing elevations. After a thorough, scientific evaluation of the remaining wild populations, he hopes to convince officials to take steps to preserve these tomatoes before they, too, are bulldozed or blasted with herbicide.
After we left the balmy greenhouse and stepped back into the chilly mist, Chetelat paused before locking the door. Nodding to the vines behind the glass, he said pointedly, “There may be a chance that fifty years from now, someone will find something really important in something that’s growing in there. That is what this is all about.”
A TOMATO GROWS
IN FLORIDA
I
n Vermont, where I live, as in much of the rest of the United States, a gardener can select pretty much any sunny patch of ground, dig a small hole, put in a tomato seedling, and come back two months later and harvest something. Not necessarily a bumper crop of plump, unblemished fruits, but something.
When I met Monica Ozores-Hampton
, a vegetable specialist with the University of Florida, I asked her what would happen if I applied the same laissez-faire horticultural practices to a tomato plant in Florida. She shot me a sorrowful, slightly condescending look and replied, “Nothing.”
“Nothing?” I asked.
“There would be nothing left of the seedling,” she said. “Not a trace. The soil here doesn’t have any nitrogen, so it wouldn’t have grown at all. The ground holds no moisture, so unless you watered regularly, the plant would certainly die. And, if it somehow survived, insect pests, bacteria, and fungal diseases would destroy it.” How can it be, then, that Florida is the source for one-third of the fresh tomatoes Americans eat? How did tomatoes become the Sunshine State’s
most valuable vegetable crop, accounting for nearly one-third of the total revenue generated?
From a purely botanical and horticultural perspective, you would have to be an idiot to attempt to commercially grow tomatoes in a place like
Florida. The seemingly insurmountable challenges start with the
soil itself. Or more accurately, the lack of it. Although an area south of Miami has
limestone gravel as a growing medium, the majority of the state’s tomatoes are raised in
sand. Not sandy loam, not sandy soil, but pure sand, no more nutrient rich than the stuff vacationers like to wiggle their toes into on the beaches of Daytona and St. Pete. “A little piece of loam or clay would go a long way,” said Ozores-Hampton. “But, hello?—this is just pure sand.” In that nearly sterile medium, Florida tomato growers have to practice the equivalent of hydroponic production, only without the greenhouses.
Because of the state’s benign weather, disease-causing organisms and insects do not die from the frosts, blizzards, and subzero cold snaps that kill
bugs and
pathogens every winter in colder growing areas. Basking in the same balmy climate as the state’s active retirees, Florida’s pests, fungi, and bacteria stay vigorous and healthy year-round, just waiting to attack the next crop of tomatoes. Those endlessly sunny winter days that the state’s tourism agency likes to tout in its advertisements also pack high levels of humidity the promoters prefer not to mention. Not so comfortable for humans, humidity is ideal for the growth of blights, wilts, spots, and molds. Hardy native weeds like
nut grass (“called that because it can drive you nuts,” one farmer told me) can easily out-compete tomato plants. Some weeds are so tough they can punch through plastic mulch laid down to suppress them. The renowned sunshine also means that rain is patchy in the winter months. Because sand retains almost no water, tomatoes have to be irrigated. And even though the daytime skies may be clear and bright, Florida is still in the Northern Hemisphere and days are short in the winter. A tomato growing in South Florida in late December gets only a little over ten and a half hours of
sunlight a day, whereas
one growing in New Jersey in June gets fifteen hours—nearly 50 percent more. Shorter days mean less vigorous growth. A tomato trying to grow in Florida also experiences debilitating temperature swings that a tomato in California or Ohio never has to face. As many a disappointed vacationer has learned, a stretch of eighty-five-degree beach days can be broken overnight by one of the notorious cold fronts that frequently blow across the state, dropping temperatures into the forties, thirties, and even lower. Add to all that the occasional hurricane that flattens the staked tomatoes and the all-too-frequent January or February frost that leaves thousands of acres of vines blackened and dead, and you have to ask: Why bother trying to grow something as temperamental as a tomato in such a hostile environment?
The answer has nothing to do with horticulture and everything to do with money. Florida just happens to be warm enough for a tomato to survive at a time of year when the easily accessed population centers in the Midwest, Mid-Atlantic, and Northeast, with their hordes of tomato-starved consumers, are frigid, their fields frozen solid under carpets of snow. But for tomatoes to survive long enough to take advantage of that huge potential market, Florida growers have to wage what amounts to total war against the elements. Forget the
Hague Convention: We’re talking about chemical, biological, and scorched-earth warfare against the forces of nature.
In tomato agribusiness’s campaign to defend their crop from the powers that would otherwise destroy a tomato field, Ozores-Hampton, who came from her native Chile to the University of Florida in the mid 1990s to do graduate work, is a key ally. She is an anomaly in the managerial and academic ranks of Florida’s tomato industry. She is not only a woman (rare enough) but an energetic, forceful, extremely fit Latina in her forties who spends her workdays toiling in the hot sun of her tomato test plots in rural areas populated by self-proclaimed red necks and crackers, then hops in her car Friday evenings and spins off to her pied-à-terre in Miami’s trendy South Beach district. Almost every other nonfieldworker I encountered in the tomato business was
white, male, and sporting at the very least a few gray hairs and/or nurturing a developing paunch, the type of guy you’d encounter on a Saturday on a golf course or in a bass boat. “They all call me ‘the Tomato Lady,’” Ozores-Hampton said. “Everyone knows who that is.”
For someone who does not fit the mold of Tomatoland’s Good Ole Boys’ Club, Ozores-Hampton has been given tremendous responsibilities. Her territory encompasses most of the state south of Tampa. She is the only university horticulturalist serving an area that has 180,000 acres of vegetables (more than half the state’s vegetable acreage). That land generates annual revenues of $1.6 billion to farmers. She is so important to the industry that when her postdoctoral work ended, a group of growers approached the president of the cash-strapped University of Florida and offered to help fund her full-time, tenure-track position for four years. Ozores-Hampton’s specialty is
soil
nutrients. She studies the cycles of plant, soil, and water interaction to determine the optimal level at which fertilizers should be applied so as to maximize production, leaving as little surplus nitrogen and potassium in the soil as possible. Excess fertilizer is a costly waste for farmers and pollutes groundwater, lakes, and rivers that feed such environmentally delicate habitats as the Everglades and Florida Bay. On the March morning that I dropped into her lab/offices in the university’s
Southwest Florida Research & Education Center near Immokalee, several of Ozores-Hampton’s assistants were upending bushel-size plastic tubs of bright green tomatoes onto lab benches. She explained that they were doing evaluations of different varieties that day to see which were the most productive. “It’s the cornerstone of agriculture anywhere in the world,” she said. “If you don’t start with the right varieties, you are not going to succeed.”
When I told her I had come hoping to gain an understanding of how the tomatoes that find their way into the nation’s supermarkets and fast food outlets are grown, she gestured toward an empty office off to one side of the lab. “You’ve come to the right place,” she said, sitting me down as if I were one of her less promising undergrads.
“If you want to understand how we grow tomatoes, you have to start at the end of the
last harvest, which around here is in April.” She explained that during the summer, a farmer can do three things with his land. Some growers put in
cover crops like
sorghum and
sudangrass, which incorporate a little organic material into the soil and out-compete any weeds that spring up. Cover crops also disrupt the cycle of
pathogens and
nematodes (microscopic worms that destroy tomatoes’ roots) by putting a different species into rotation with what would otherwise be a monocrop—tomato after tomato after tomato. In addition, cover crops serve to capture and store the nitrogen and other fertilizers left behind after the growing season. Instead of using cover crops, farmers can also simply leave the fields fallow. Weeds come up, and they use the herbicide Roundup to kill the weeds. Still other growers choose to flood the fields, drowning weeds, pathogens, and nematodes.
Whatever route a grower chooses, the land lies fallow for sixty to ninety days. By July, it’s time to start preparing for the next season’s crop. Step one is all but identical to the first stage of erecting yet another Florida condo development or shopping mall. Heavy equipment removes all traces of vegetation, leaving a perfectly flat, dry rectangle of pristine sand. Before anything else can happen, that sand has to be
watered somehow. And fortunately, water is one area where nature gives Florida farmers a break. Although rain can be unpredictable in the winter, the state is awash in ground water and crisscrossed with canals and ditches meant to drain that water from what would otherwise be swampland.
“Good thing, too,” Ozores-Hampton said, “or you and I would be sitting underwater right now.” The shallow layer of sand sits atop impermeable “hard pan,” made up of clay and compacted organic matter. Some farmers use traditional
drip
irrigation, where hoses with small holes are run between plants to deliver a trickle of water, but most growers in South Florida employ a system unique to the area called “
seepage irrigation.” They simply pump water into canals and
ditches that cross their fields. The water sinks down to the impermeable hard pan, and with nowhere else to go, seeps outward, moistening the sand from below. If a heavy rain falls, the farmer pumps water out of his field back into a larger canal, lowering the water level beneath his plants’
roots and maintaining optimum
moisture. “To do this type of irrigation, you have to have water, you have to have sandy soil, and you have to have an impermeable layer to keep that water from draining away,” said Ozores-Hampton. South Florida is the only agricultural area in the world that has such conditions.
For such a system to be effective, crops must be grown in
raised beds that are covered in plastic to slow the evaporation. To fashion these beds, Florida growers use principles familiar to any child who has constructed a sand castle: Too little moisture and your castle disintegrates immediately; too much and it slumps into a pile of shapeless muck. But if the moisture level is just right, you can construct a castle with steep-sided moats, crenellated walls, and smoothly rounded turrets. Once they have the right
concentrations of moisture in tomato-field sand, farmers inoculate it with a “
bottom mix” of fertilizer containing about 20 percent of the nitrogen and potassium the plant will need. GPS-guided tractors equipped with laser levelers carve straight lines of perfectly flat-topped beds that are about three feet wide and raised eight inches above the trenches that run between them, a process that is called “
pulling beds.” Another tractor follows closely behind. Its job is to apply the remaining 80 percent of the nitrogen and potassium, called the “
hot mix,” into two deep grooves that it gouges on the outside edges of the bed. The tomatoes’ roots grow to the edge of the deposits of soluble fertilizer and absorb the exact amount they need over the course of the season, growing farther into the deposit as they deplete one area. “The roots are intelligent. They know where to grow,” said Ozores-Hampton.