Build your trellis for the future
Fixing a fallen trellis is costly and might not even be possible.
Planning and building the trellis is one of the most important aspects of establishing a high-density orchard. Your orchard literally depends on it.
Bill Johnson, with Wilson Irrigation and Vineyard Supply in Wenatchee, Washington, said receiving a call from a grower whose trellis has collapsed in the middle of harvest is one of the most pitiful situations he has to deal with. “It’s a mess, and it’s expensive.”
Growers do lots of planning to ensure that they choose the right site, plant the right trees, and install the right irrigation system. They should also devote time to make sure they have a sound trellis system, Johnson said, and that means choosing the right anchors, poles, wire, and post spacing for the planting.
Kent Waliser, manager of Sagemoor Farms in Pasco, Washington, said when planting trees on dwarfing rootstocks like Malling 9 or M.26, the grower has to provide the support that the tree can’t give itself. The trellis must be strong enough to support a full crop of fruit as well as the trees.
If a grower misses one of the critical trellis design criteria, there’s a risk that it will come down. A sandy soil will not support the trees or trellis as well as a silt loam, and tree height makes a difference, too. “It’s just like sailing a boat,” Waliser said. “The taller it is, the more wind it will catch, and the easier the whole thing will come over.”
Waliser said it’s most important that a trellis be installed correctly. It’s a good idea to train your crew to do it. They have a vested interest in its success because they’re not going to want to have to deal with a broken trellis. However, if it is a one-time investment, it might be best to hire a contractor, but you should know enough about how to do it to know if they are doing it right. Fixing a fallen trellis is expensive and might not even be possible.
Waliser said precisely spaced posts and trees are becoming increasingly important with the prospect of more mechanization in the orchard. The trellis must be even more precisely installed than the trees because it is creating the architecture that the grower will have to deal with by mechanical means later.
Growers with very precise systems will be the first to adopt whatever technology comes along, he believes. Small growers who have imprecise or inconsistent blocks will be at a disadvantage because most of the future advances in terms of efficiency and cost cutting are going to come through mechanization or mechanical aids.
“If half your orchard is on V trellis and half is vertical, and you only have 40 acres of each, and you need 100 acres to adopt the next technology, you’re out of the game,” he said. “If you’re a small grower, it’s even more paramount that you adopt a certain spacing or tree architecture.”
“Every block you plant from now on should be with that in mind—that you’re going to be able to adopt the technology. From here on out, you just have to get very precise in putting those pieces in the ground, because you’re not doing it for the technology you used ten years ago. You’re doing it because, hopefully, there will be something developed in the next five years, and your system will not be out of date when the technology shows up.”
The major trellis components are described on the following pages.