Trellising Your Trees

Trellising is the best support system for high-density orchards of any size; it allows dwarfing trees to be grown close together in a “tall spindle” form that provides good light penetration and high productivity. A home gardener who wants just a dozen dwarfing apple trees would not be wrong to set up a small trellis in their back yard.

There are two main types of apple trellis: multi-wire and single-wire trellises.

• A multi-wire trellis has a horizontal wire every 2-3'. This has the advantage of providing support for lateral branches, thus enabling increased crop load. The end product is a “fruiting wall.” The horizontal wires also protect against tree twisting and snappage. The disadvantage of this system is that the trellis does not allow walk-through. This will be an important consideration if you are planting apples for a U-pick operation.
• Single-wire trellising means running a single wire along the top of your trellis posts. Single-wire trellising enables walk-through, but it requires additional supports: each tree is trained up a bamboo or metal pole that is fixed to the top wire.

Whether you choose single-wire or multi-wire trellising, your basic trellis frame will be the same. Here are a few important points to consider before purchasing materials or beginning to build.

• The anchor system is the most important part of the trellis. The anchor/tie-back post should be pounded about 5' deep. Both the end post and the tie-back post should be 5-6" diameter.
• Always overbuild rather than underbuild.
• Line posts should never be over 30' apart. These should be 5" posts, at least 25% in the ground. The length of your posts and the depth of pounding will determine the height of the top wire. That is, a 10' pole pounded 2.5' deep will render a top wire 7.5' high.

There are many great on-line tutorials that will help you plan and build an apple trellis. Here are a few:

• Penn State Extension
• GoodFruit Grower Tips
• Cornell Tips