I have fond childhood memories of summer picnics under a majestic pecan tree on our family farm near Hemingway. Many generations have shared such memories, since these nut-bearing trees can live more than 200 years. Our tree’s life was cut short by Hurricane Hugo, but South Carolina is blessed with many picnic-worthy pecan trees.
Pecan trees (I say pee-can, not pe-kahn) are truly dual purpose. Besides being attractive, native shade trees, they also produce prized and valuable nuts. Requiring ample space to reach their standard 70- to 120-foot height and 80-to-120-foot spread, they are worthy of consideration for their beauty alone. That’s a plus, since it can be frustrating to produce a reliable harvest of quality nuts.
If the savory nuts are your primary ambition for growing pecan trees, you can boost your chances of a good fall harvest. Starting from scratch? Be sure to buy at least two varieties with overlapping bloom cycles. Choose varieties that are resistant to pecan scab, the major disease that limits nut production. Within these constraints, the best varieties include Cape Fear, Curtis, Elliot and Stuart. New plantings will need six to 12 years to become productive.
The next step to ensure good pecan production is to fertilize properly. Improper soil fertility is the biggest factor in underperforming trees. It causes non-uniform bearing (on and off years) and early nut drop.
The results of a soil test will help determine fertilizer recommendations and ensure a soil pH in the 6 to 6.5 range. For mature trees, follow the general rule of six pounds of 10-10-10 fertilizer per inch of trunk diameter (e.g., a tree with a 10-inch trunk diameter would receive 60 pounds of 10-10-10). Because pecan trees have a high zinc requirement, use specialty pecan fertilizers—typically 10-10-10 with 2 percent zinc. Broadcast the fertilizer beneath the tree’s canopy in late February.
Insects and diseases are the next biggest enemies to producing quality nuts. They’re also the most difficult to manage. Pest and disease control call for excellent sanitation practices, because the sheer size of mature pecan trees makes spraying them in the home landscape practically impossible.
Be proactive with sanitation. Keep the area under trees clean by removing and destroying fallen leaves, twigs, nuts and shucks to prevent the carryover of diseases, like pecan scab, from one season to the next and to break the life cycle of insect pests like the pecan weevil. Perform this work weekly during the growing season for best results.
Despite our best efforts, a bountiful pecan harvest just isn’t possible every year. Some factors are out of our control. Pecans are wind pollinated, so rainy weather during bloom will reduce pollination and nut set. Summer droughts often result in improperly filled nuts and lead to early leaf drop, decreasing production the following year as well.
Despite their challenges, pecan trees are a worthwhile investment in the landscape. Enjoy them for their shade and majestic form, and follow the tips above to be rewarded with tasty pecans most years.
S. Cory Tanner is an area horticulture agent and Master Gardener coordinator for Clemson Extension based in Greenville County. Contact him here.