JOHNSTON, S.C. —
Four generations of growing peaches in South Carolina have taught the Yonce family where to plant trees for the best crop, how to prune for the best yield and what to do to in a late freeze to prevent a devastating frost.
But what the Yonces and thousands of other peach growers still don’t know is this: How does a peach know when the cold winter weather is over and it is time to grow?
A group of Clemson University researchers is trying to find the answer.
“It’s an interesting phenomenon,” Clemson plant biologist Doug Bielenberg said. “These plants count the cold hours and days. If it gets warm for a bit, they stop, and then they pick up counting where they left off.”
The concept has been known for decades in the plant world as chill hours. What Bielenberg is trying to figure out is how a plant has this memory for cold weather and which genes control the process.
If scientists learn out how to manipulate the peach’s chill hours, the research could be groundbreaking. By reducing the hours, plants could be grown in a large number of climates across the earth. For peach farmers, it could mean getting larger, juicer varieties into stores faster, Bielenberg said
Peaches are ideal for this kind of research because they have a fairly simple genetic structure and are closely related to a number of other fruits, such as berries, apples and plums, Bielenberg said.
Peach farmers are watching the research carefully. Blooms are just starting to come out on the earliest varieties, meaning Larry Yonce will again hang on to the weather forecast through April, when he can be sure freezing temperatures are over until the fall.
“The weather controls our destiny, basically,” said Yonce, who has been growing peaches for four decades. The family business is J.W. Yonce & Sons farm, founded by his grandfather in 1932 in Edgefield County.
Yonce’s 3,000-acre site is the second-largest peach farm in the second-highest peach-producing state in the country, behind California. The area produced cotton for decades before the boll weevil wiped them out. Farmers along the rolling hills of the ridge of South Carolina eventually turned to peaches.
The fruit was perfect for the area. Winter nights are cold enough for the chemical reactions that make peaches sweet, but not cold enough to kill the fruit as it grows. Peaches later need warm to hot weather for the fruit to mature. That’s why the Georgia joins California and South Carolina as the nation’s leading peach-producing states.
Research from Clemson and the University of Georgia has helped up farmers considerably over the years. One of the Yonce farm’s best-sellers is a peach, developed through years of breeding, that doesn’t need as many chill hours so it ripens in May, but has the color, texture and sweetness of peaches that used to not hit the market until July.
But with all the science, there is still plenty of uncertainty in peach farming. Last year’s crop looked promising until a warmer-than-usual March and April left the fruit without enough chilling hours to reach its best taste and appearance. And peach farmers like the Yonces get downright depressed when the April 7 freeze of 2007 is brought up. Temperatures fell into the low 20s on the ridge. The state produced just 9,000 tons of peaches that year, compared with an already fairly sparse crop of 60,000 tons the year before.
In the family’s orchards, Chris Yonce points to blooms already on the tree. What should become a peach is already inside, no larger than an eyelash and about a quarter of the length. In about a month, roughly a third of the blooms will be removed from the tree by hand to maximize yield, a process that will go on for weeks on each of the farm’s roughly 500,000 trees.
Yonce takes his knife and cuts open a bloom. The tiny fleck inside is black. That flower would yield no peach, but Yonce wouldn’t have known until after the pruning.
“Growing peaches is like legalized gambling,” he said.
And that’s something that science will likely never be able to change.
National, International News
Related Photos
-
South Carolina Peach Council Executive Amy London, left, and peach farmer Chris Yonce, right, look at peach blossoms on Yonce's farm on Friday, Feb. 22, 2013, in Johnston, S.C. Peach blossoms have just started to sprout as peach farmers enter the critical time of the growing season. (AP Photo/Jeffrey Collins) The Associated Press
Discussion
Clemson research tackles peach-growing mystery
- National, International News
-
-
Wave of attacks kills at least 95 in Iraq
A wave of attacks killed at least 95 people in Shiite and Sunni areas of Iraq on Monday, officials said, pushing the death toll over the past week to more than 240 and extending one of the most sustained bouts of sectarian violence the country has seen in years.
-
Arias attorneys will put one witness on: Arias
Complaining that Jodi Arias’ sensational murder case has become a modern-day “witch trial,” her lawyers tried to quit in the middle of the death-penalty phase Monday, then said they will call only one witness: Arias.
-
Oklahoma twister tracked path of 1999 tornado
Monday’s powerful tornado in suburban Oklahoma City loosely followed the path of a killer twister that slammed the region in May 1999.
-
Dozens killed as tornado ravages Oklahoma City area
A powerful late-afternoon tornado leveled much of this Oklahoma community Monday, killing at least 51 people. Reporters on helicopters flying above the scene described the scene as “devastating.”
-
Today in History for Tuesday, May 21, 2013
Today is Tuesday, May 21, the 141st day of 2013. There are 224 days left in the year.
-
Several Republicans weigh challenge to Barrow
Now that Rep. John Barrow has turned down a campaign for the U.S. Senate, the challenge ahead for the Deep South’s last white Democratic congressman will be to defy the odds a second time by winning re-election in an eastern Georgia district that was drawn to ensure his defeat.
-
‘Trek’ does $70.6M but falls short of studio hopes
“Star Trek: Into Darkness” has warped its way to a $70.6 million domestic launch from Friday to Sunday, though it’s not setting any light-speed records with a debut that’s lower than the studio’s expectations.
-
Syrian troops push into strategic rebel-held town
Syrian troops pushed into a rebel-held town near the Lebanese border on Sunday, fighting house-to-house and bombing from the air as President Bashar Assad tried to strengthen his grip on a strategic strip of land running from the capital to the Mediterranean coast.
-
Taylor Swift wins 8 trophies at Billboard Awards
Another day, another domination for Taylor Swift: She was the red hot winner at the Billboard Music Awards.
-
Tornadoes level homes in Okla., 21 injured
One of several tornadoes that touched down Sunday in Oklahoma turned homes in a trailer park near Oklahoma City into splinters and rubble and sent frightened residents along a 100-mile corridor scurrying for shelter.
- More National, International News Headlines
-
