Horticulture Term Project

Asked October 15, 2019, 8:01 PM EDT

I'm a student at Chemeketa, and I'm currently taking a course on growing fruit in the Willamette Valley. For our term project, we're tasked with choosing a fruiting crop, and creating a plan on how we would establish a 20 acre farm of that crop. Wanting to be ambitious, I decided on olives. I'd like to ask the horticulture experts some questions: 1.) How many trees are typically planted per acre? 2.) What varieties/cultivars seem the most promising? 3.) What varieties/cultivars are good for what mode of process? (Like pickling vs. oil vs. tin canned) 4.) How labor intensive are olives? What the typical cost of labor per acre? 5.) What pests are the most concerning, and how are they managed? 6.) Are olive trees put on any kind of rootstock? Is there any other info the experts have that they think I may need to know? Thank you!

Marion County Oregon

1 Response

Great questions, all! And because olives are so new in Oregon, we don't have answers to each of them. At our last count, there were only about 20 growers in the state.

Most, if not all, of the olive growers in Oregon do not have more than 15 acres of olives, so 20 acres for your project is ambitious, indeed. In Oregon, olives are typically planted in 10'-20' spacings. The OSU Olea Project is currently conducting research trials to determine the most cold hardy cultivars. We anticipate that trial to be planted out in 2021. As of now, we do not have any recommendations for promising cultivars. We can share the most common cultivars planted in the state, though keep in mind that most common is not synonymous with best suited. The most common cultivars are:

  • Arbequina
  • Leccino
  • Frantoio
  • Pendolino*
*Of note, Pendolino is normally planted as a pollenizer.

Most of the olives grown in the state are used to produce olive oil. Our growing season is short and olives may not fully ripen before the end of the season. They are often picked while still green.

Anecdotally, labor is the greatest cost. Some growers use branch shakers, but most pick by hand. Many growers have friends and neighbors pick on a volunteer basis. Some hire crews. We don't have any data on labor costs at this time.

Oregon does not yet have many of the troublesome olive pests found in California. The most common pest we have found in our research plots is olive scale. We manage scale by destroying the plant it is found on. We do not yet have data on pest pressure or management practices in commercial olive groves.

Olives are not grafted to rootstock.

For additional olive questions, I suggest you reach out to the principal investigator of the Olea Project, Javier Fernandez-Salvador. javier.f-s@oregonstate.edu