How to grow citrus in California
by Nan Sterman
Citrus harvest seasons
To enjoy citrus year-round, here are some varieties to try and their harvest:
Washington navel oranges
Improved Meyer lemons
spring, summer, winter
California and citrus are pretty much synonymous. Orange County is named for the fruits that blanketed the Southland more than 100 years after Spanish missionaries arrived with the first trees.
In 1873, Southern California farmers began planting Washington navel orange trees and soon citrus grew from the coast to the desert. Reminders of those orchards still exist in the backyards of housing tracts and on remnant agricultural lands.
The citrus industry is still strong today, from the southern border to the foothills that surround Sacramento. In Auburn, Calif., the annual Mountain Mandarin Festival celebrates the November Owari Satsuma mandarin harvest.
How to grow citrus
Plant citrus from spring to fall, preferably in well-draining soil. If you have clay soil, plant it in raised beds or large containers. Make a mound about 6 to 10 inches higher than the surrounding soil. Plant in the mound, covering the surface roots with no more than one-half inch of soil. Then water the soil so it's saturated several feet deep. Mulch beyond the branch canopy, not below it. Don't plant beneath citrus trees as they'll compete for water and nutrients.
Expect citrus to bear fruit in about three years if it's fed sufficiently. Throughout the first year, water young plants deeply and regularly to keep soil moist but not wet. After that, water deeply every week or two from spring to fall and in long, dry spells during winter.
Citrus doesn't require pruning except to remove dead wood. Prune to shape and to keep fruit off the ground, but don't go overboard. Bark exposed to direct sun will burn.
What to grow where
According to John "Cedar" Seeger of Four Wind Growers in Fremont, citrus can be grown in the ground from the Mexican border east into the desert and in gardens below 1,500 feet elevation as far north as Redding. In colder areas, Seeger suggests growing dwarf citrus in pots and moving them to a protected spot during winter. Kumquats and mandarins are the most hardy of citrus plants. Mexican limes are the most frost-sensitive.
In January 2007, a freeze in Southern California caused extensive citrus damage. My garden near San Diego dipped down to 17 degrees. The leaves and fruit on my Mexican lime turned the color of straw, but recovered by spring. The Oroblanco grapefruit and Nagami kumquat trees were unscathed, though the kumquat fruits were slushy. My mandarin and orange tree leaves burned but recovered quickly.
Nan Sterman is author of "California Gardener's Guide Volume II." She's a gardening expert, communicator and designer who has long grown an organic garden of plants that both feed her family and beautify her yard.