August 04, 2006

Nothing is Ever Set in Stone (Fruit)

Growing peaches and other stone fruit, while rewarding, is not a predictable endeavor. “The challenges change every year,” observes Victor Martino of Bella Viva Orchards.

“Sometimes it’s hail, sometimes frost, rain, heat, brown rot…you really have to maintain your awareness.” Year after year, farmers put their hearts and their sweat into the land, working toward a bumper harvest, all the while knowing that the outcome is largely beyond their control. It’s not surprising that farmers talk a lot about problems: the weather, their equipment, wholesale prices, plant diseases…if you are ever curious about the challenges of farming, you will have no trouble finding a grower to give you an earful. You will also learn that farmers are inventive and resourceful, for though there are many problems, there are even more solutions.

Any stone fruit grower will tell you that this year has been a tough one. Peaches and many other stone fruits were in full bloom during spring’s persistent rains and the moisture created an ideal habitat for brown rot, which destroyed blossoms. Without blossoms, there can be no fruit. Many conventional orchardists solved the problem with chemical fungicides. There are also substances in the organic toolbox to combat brown rot, such as a spray of sulfur and micronized rock dust that Steven Kashiwase of Kashiwase Farms uses. Still, there is some fruit loss.

Tory Torosian of Tory Farms speculates that his scant harvest of some peach varieties is due to a warmer than average winter. Many fruit trees have a winter chilling requirement, known as “chill hours.” Calculation methods vary, but chill hours are roughly the number of hours below 45 degrees Fahrenheit that a tree must endure for its buds to break dormancy and for blossoms to develop. Tory says that some of his varieties need 800-900 chill hours, and he guesses that they got fewer than 700 hours this winter.

The late rains had an additional effect for Tory Farms: they washed off the copper that Tory (like many peach growers) uses to prevent a disease called peach leaf curl, which can diminish peach yield. The curl is so severe this year that it is damaging not only the leaves of his trees, but also the wood.

This year, Victor Martino is concerned about mites, which suck the juice out of peach leaves and reproduce like crazy. They can defoliate an entire tree. Victor is working to establish habitat on his farm for natural predatory insects such as the spider mite destroyer, which eats the harmful pest. However, he has only recently converted some of his peach orchard to organic production methods, and natural insect populations are not yet well established. Victor plans to control the mites with another beneficial insect, the western predatory mite, which he purchased from a supplier.

Fitzgerald Kelly of Fitzgerald’s is also seeing unprecedented numbers of mites in his orchard this year. To combat them, he first tried a bit of folklore he’d heard from a farmer friend: using a spray rig, he misted the trees with the coldest water he could get, during the hottest part of the day. Not only did it not work, the mites seemed to love it! In the end, Fitz eliminated the mites by spraying a miticide. He sprayed every other row, using half the volume of chemicals normally recommended.

Perhaps the most bizarre stone fruit problem we’ve heard about this year was also reported by Fitz Kelly. Around the end of April, he observed slugs climbing into his nectarine trees and eating his fruit. Fitz thinks that perhaps the moisture from this year’s incessant rains, combined with his lush cover crops, created perfect slug habitat. Fitz’s simple and clever solution to his slug problem was to thin his fruit, which he does every year anyway. He dropped the immature fruit onto the ground, providing the slugs a convenient food source that didn’t require a long and slow journey up a tree trunk.

While plants do their best to flourish, nature always presents the farmer with obstacles. Farmers are among the smartest and most observant people we know, but technology and human ingenuity can only go so far. Harvest is never guaranteed, so carpe Prunus persica—seize the peach!

About CUESA

CUESA (Center for Urban Education about Sustainable Agriculture) is dedicated to cultivating a sustainable food system through the operation of the Ferry Plaza Farmers Market and its educational programs. Learn More »