Olive Orchard Specifications by Sierra Gold Nurseries

Tree Spacing & Planting
Super-high Density Olive Orchards are most commonly planted at spacings of 4’-6’ in between the trees and 12’-13’ in between the tree rows. This spacing has been determined to be the most efficient considering sunlight penetration, equipment use, and tree shape while maximizing fruit yield. See Tree Spacing chart to determine the number of trees per acre with typic spacings. Spring and Fall have proven to be the best seasons to plant, allowing the small olive trees to establish themselves before either the heat of summer or the cold of winter. However, growers have successfully planted orchards almost year-round provided that irrigation systems are in place and ready to work immediately after the trees are planted. Olive trees are semi-deciduous, so trees will arrive from the nursery in small 3”x3”x4” pots, varying from 12” to 24” in height for easy transplanting to the field. There are 20 trees per flat.

Orchard Irrigation
Typically, Super-high Density Olive Orchards are developed using drip irrigation with in-line emitters. Emitters can either be continuous along the drip tape to create a solid band of irrigated coverage, or they can be placed immediately next to trees. Typically, emitters deliver .50 g.p.h. each. Drip tape can either be buried, on top of the ground, or suspended from the wire trellis system.

Tree Training
Typically, growers install a bamboo, wood, or metal stake at the time of planting with each tree. The tree is tied to the stake every 10”-12” to promote the growth of the central leader. Each tree stake is secured to a single-wire trellis system installed down every tree row. The wire trellis is installed 4’-5’ above the ground, and is anchored at the end of each tree row and connected to intermediary line stakes down the row. Wood or metal can be used for the trellis anchors and line stakes. While the trellis system will not support the crop load, it is important to keep each tree upright and maintained in a straight hedge.

Pruning
Trees in a super-high density orchard are pruned to a central leader, with an emphasis on fruitwood rejuvenation. The tree canopy is kept to about two feet above the orchard floor and topped to a height of 6’-8’. Mechanical topping is easily achieved in this pruning system, while all other pruning is currently being done by hand in existing orchards.

Bloom
At full bloom, typically mid-late April to early May, flowers are delicately
poised for pollination, a critical event to determine fruit set. Super-high density olive varieties are considered “self-fertile” but can also be cross-pollinated. Orchard trials are indicating that having a small percentage (10%-20%) of differing varities within an orchard will help cross-pollination and result in better yields. With self-pollination, the pollen simply falls from anther to pistil in the same flower. Wind is the primary agent of olive cross-pollination, as bees are not universally present in sufficient numbers or attracted to olive flowers to be a factor in pollination. In addition to pollination, environmental conditions have a bearing on fruit set. Wind, rain, and temperature will affect fruit set.

Harvest
One of the biggest advantages to super-high density orchards is the ability to efficiently harvest the crop with mechanical over-the-row grape harvesters. A typical grape harvester with a bank-out tractor wagon can be used to effectively harvest 1 to 1.5 acres per hour. This is a substantially more efficient and less costly method versus hand harvests, shaking, or any other method used to date.