Plant spacing is crucial to the productivity, maintenance and renovation of an orchard over time. Appropriate plant spacing depends on the site characteristics (topography, soil type and quality, drainage, site microclimates), inputs of water, fertilizer and pesticides, the hazelnut varieties selected, and the location of the trees designated to be pollinizers.
Trees should be planted and spaced in north to south rows for better sun exposure into the canopy.
Common plant spacings:
1. Traditional:
Trees are spaced 6 x 6 m (267 trees/ hectare) to 5.5 x 5.5 m (331 trees/ hectare). These spacings generally allow for large plants and possibly multiple stems. These are solid permanent spacings for most soil types and hazelnut varieties.
2. Double Density
Trees are spaced 3 x 6 m (538 trees/ hectare) or 3.6 × 5.5 meters with 496 trees per hectare, with thinning to a triangle of about 6, 6.4, or 6.7 meters. The extra trees or “interplants” are only temporary at establishment and are thinned after 8-12 years to increase the space for maturing trees to maintain productivity. The production/ tree in a high-density orchard is nearly the same as that from a traditional-density orchard for the first 5-6 years, as the yield per hectare increases in proportion to the higher number of trees. The interplants should never be the pollinizer variety as they will be thinned out over time within the orchard. Spacing should be in a zigzag pattern to give trees the optimal space (i.e. two parallel rows are planted half the planting distance in row offset).