Some people just won’t give up on a dream. For Stan McKenzie, of Scranton, S.C., it was growing citrus fruits. After a number of years and failed attempts, he is now known as “The Citrusman.”

Although winters are reasonably mild at McKenzie Farms, the Zone 8 location is hundreds of miles from traditional citrus- growing regions. In January, nighttime temperatures may drop into the teens, and it isn’t surprising that McKenzie’s boyhood citrus trees succumbed the first winter. In the 1980s he saw flourishing grapefruit trees further south in Charleston, S.C., and research led him to the Satsuma variety, a variety of mandarin orange that originated in Japan. His first came from Alabama.

Going commercial

For years, while growing other fruits and vegetables for direct marketing, McKenzie enjoyed learning about cold-hardy citrus and collecting seeds from across the globe. Word about his success with citrus spread, and the demand for plants led him to open a nursery in 1999 where trees are propagated by grafting or cuttings.

He now has more than 60 varieties, but Satsumas remain McKenzie’s favorite.

“Satsumas are high-quality, tasty and offer ease of growing,” he says. He adds that they are hardy to 13 degrees, and he is acquainted with successful growers of the variety as far north as Cary, N.C., and Virginia Beach, Va.

Among McKenzie’s Satsumas is the Kimbrough that was discovered after a killing freeze in Louisiana. It is believed to be hardy to 12 degrees. Two releases from Louisiana State University, Louisiana Early and Early St. Ann, ripen several weeks earlier than other Satsumas.

The Yuzu, another cold-hardy citrus from Japan, has been reported to survive temperatures as low as 5 degrees. Its lemon-lime-grapefruit flavor adds zest to seafood and sherbet.

The Ten Degree Tangerine hasn’t had to battle temperatures quite that low at McKenzie Farms, but it has handled 13 degrees beautifully. Developed in Texas, this thorny tree offers fruit with a flavor both sweet and tart.

Meiwa and Nagami kumquats mature in late fall. The dormant trees can tolerate nights in the mid-teens. Kumquat and Satsuma mandarin orange form a hybrid known as Nippon orangequat, producing fruit with a sweet orange taste that matures in late autumn. The Thomasville Citrangequat was an early breeding attempt to develop a cold-hardy variety. It first fruited in Thomasville, Ga., and is a prolific bearer of kumquat-orange-flavored fruit. Established trees may grow to 15 feet in height and can survive temperatures as low as 5 degrees.

McKenzie also grows several lemon and lime varieties. Harvey lemon has some cold tolerance. The Taichang lemon, a cross between the Ichang and Taiwanica lemon, doesn’t shy away from temperatures in the mid-teens. The Ichang survives down to approximately 20 degrees and bears lemons almost as large as grapefruit. But if you need a lemon tree that can take sub-zero freezes, Bitter lemon is what you’re looking for. New Englanders have reported success with it and estimate hardiness to 5 degrees below zero. Limes are the toughest to grow in chilly climates; Eustis limequats are the surest bet.

Citrus Organizations and Resources
Citrus Growers’ Forum
http://www.citrus.forumup.org
Texas A&M University Horticulture Program
http://www.aggie-horticulture.tamu.edu/citrus
University of Florida Citrus Research and Education Center
www.crec.ifas.ufl.edu

Citrus Events
Southeastern Citrus Exposition

Cold-Hardy Citrus Tree Suppliers
Ponds & Plants
Dayton, Tenn.
423-570-1234
McKenzie Farms
Scranton, S.C.
843-389-4831
Woodlanders Nursery
Aiken, S.C.
803-648-7522

The McKenzie nursery offers a Bloomsweet grapefruit that can tolerate mid-teen temperatures. Citrumelo, a hybrid of the trifoliate orange and grapefruit, produces a fruit with a grapefruit-like taste and has been successful as far north as Tennessee. Citrange, a hybrid of trifoliate orange and sweet orange, is another winner for colder regions as it can withstand temperatures down to zero degrees. McKenzie grows Benton, Rusk and Morton citranges and also handles Citrandarins, a hybrid of mandarin and trifoliate orange.

In “Citrus for Southern and Coastal Alabama,” Arlie Powell and Dave Williams, extension horticulturists at Auburn University, recommend using varieties that ripen early in cooler areas. Defining early as September through November, all types of Satsumas are appropriate. Armstrong Early, Brown’s Select and Port Neches can be harvested even sooner. Clementine tangerines and tangerine hybrids Robinson, Sunburst and Lee also mature in the summer and fall. Early sweet oranges include Navel-Washington, Navel-Cara Cara, Hamlin and Ambersweet. Lime hybrids Eustis, Lakeland and Tavares, along with Meyer lemon, can be plucked year-round.

McKenzie’s newest venture is the pick-your-own market. He planted a 135-tree orchard, prominently Satsuma, in the spring of 2007 and plans to open it to pickers in 2009.

Growing citrus outside the citrus belt

Most traditional citrus-growing regions aren’t 100 percent frost-free, and even Florida growers are prepared with a variety of cold-busting systems. What does a grower face in locales that are certain to have freezing conditions?

“I tell clients there are three things to worry about: December, January and February,” McKenzie says.

A typical January night at McKenzie Farms hovers around the freezing point, and McKenzie is prepared to baby his trees through the chill. He installed microjet sprinklers over each tree in the pick-your-own grove and has found that system to provide good freeze protection. He also hangs Christmas lights about to add a bit of warmth. He suggests planting near the south side of a structure when possible. He has shipped citrus trees as far north as Vancouver, B.C., and believes that those who are willing to invest in cold protection can be successful in northern climates.

Powell and Williams say that cold protection is most essential for trees less than four years old. Young trees should be banked with about 15 inches of clean soil. Soil banks protect only the portion of the trunk that is covered and should be removed when the chance of freezing passes. Another method is to wrap trunks with commercial wraps or an insulating material such as foam rubber.

Information about cold-hardy citrus isn’t easy to find. McKenzie recommends “Hardy Citrus for the Southeast,” a book written by Tom McClellan that addresses zones 6 through 9.

Jenan Jones Benson is a freelance writer based in Greensboro, N.C.