Before purchasing trees, evaluate the pollination requirement of the given fruit crop. Place pole-type pollinators every 60 to 120 feet in every row, with adjacent rows offset. The honey bee is the most important carrier of pollen. All varieties of apples require some cross-pollination.
All sour cherries are self-fruitful.
Common varieties of nectarines and most peaches grown in Colorado are self-fruitful. Most fruit trees need cross-pollination for good fruit set, and you may need to buy more than just one variety. For pollination, place pole-type pollinators every 60 to 120 feet in every row, with adjacent rows offset. These pollinizer trees, trained as a pole-type or slender spindle, take up little or no productive space in the orchard but give maximum fruit set potential. For backyard trees, a pollen source, such as a neighbor's crabapple tree, should be no more than 100 feet away.