Pruning Apple Trees

Recently, I joined about forty home gardeners for a presentation on fruit tree care. The question & answer session was conducted by Oren Martin, manager of the Alan Chadwick Garden at UC Santa Cruz (www.alan-chadwick.org) and Matthew Sutton, owner of Orchard Keepers, in Santa Cruz (www.orchardkeepers.com).

The event was hosted by the Santa Cruz’s Probuild Garden Center, which has an impressive collection of bare-root fruit trees, so some questioners were interested in selecting, planting and first-year care of these trees. Others—including myself—wanted to know about pruning their existing trees.

Martin and Sutton emphasized the goals of pruning: to control tree height, allow sunlight and air to reach the center of the canopy, remove poorly place branches, and renew older branches. They described and demonstrated two basic kinds of pruning cuts.

Thinning cuts remove a branch completely, with no regrowth. These cuts open the tree to more sunlight, and create and maintain fruit buds. Thinning cuts should not be made flush, but should retain the branch’s collar, which is the tree’s defense against the invasion of microorganisms.

Heading cuts stimulate the branch’s growth, shape the tree’s structure, thicken branches, or induce lateral branching. These cuts remove the branch’s terminal bud, which produces a hormone (“auxin”) that inhibits the growth of lateral buds. This phenomenon is called “apical dominance.” Removal of the terminal bud stimulates regrowth at the bud below the cut.

Heading cuts vary with the amount removed from the branch. A heavy cut removes 50% of the previous season’s growth, while a light cut (leader tipping) removes less than 25% of that growth.

This session was helpful, but left much to be learned. UCSC experts will offer three workshops of value for home orchardists.

Fruit Trees 101: Basic Fruit Tree Care will be offered twice. The first will be on January 18, 2014 at the Sierra Azul Nursery and Gardens, in Watsonville. The second will be on January 25th, at the UCSC Farm. Each two-hour workshop will cost $40 for general public. For details, browse to the website of the Center for Agroecology and Sustainable Food Systems, or call 831-459-3240

Basic Pome Fruit Pruning, with a Focus on Apples and Pears, will be offered from 10:00 to 12:00 on Saturday, February 1st, at the UCSC Farm. Orin Martin and Matthew Sutton will advise on pruning your fruit trees to maximize health and production. The cost is $40 for general public, $30 for Friends of the Farm & Garden members. To register, visit http://pruningpome.bpt.me/, call 831-459-3240, or email casfs.ucsc.edu.

More

An excellent information source for home orchard gardeners is the University of California’s website, The California Backyard Orchard. The section on Pruning & Training complements this column; several other sections provide expert advice for other aspects of the care of home orchards.