Whether you live in the northeastern part of South Dakota or in Sioux Falls to the southeast, several varieties of pear trees do well: Parker, Ure and Golden Spice. All will be ready to pick in September. The Luscious variety, with a flavor similar to the Bartlett, was developed at South Dakota State University and should be on every South Dakota gardener's planting list. Almost all of South Dakota is in USDA Hardiness zone 4.
Plant the tree in full sun and at least 25 feet from other trees. Pear trees lack winter hardiness and should be planted in well-protected locations.
Give the pear tree 1 to 2 inches of water per week. If the weather is particularly dry in eastern South Dakota, water more frequently. Stop watering at the first frost and resume when the frost has passed, in the spring.
Fertilize the pear tree in early spring, just before the buds open. Use 1/8 pound of ammonium nitrate per year of the tree's age. Apply the fertilizer to the soil and spread it from the base of the tree to the width of the canopy. Do not allow the fertilizer to touch the bark of the tree.
Prune the pear tree carefully. Because of their susceptibility to fireb light, pear trees should not be over-pruned. In eastern South Dakota wait until after the harvest; October is ideal. Remove any suckers from the base of the tree and branches that form a narrow angle with the trunk (those that are tending to grow straight up or at a slight angle).
Inspect the pear tree for insect infestation. Eastern South Dakota trees are attractive to psylla, a small red or green bug that will suck the juice from the tree. Although the insect is difficult to see, it secretes a substance that will mold and turn black. According to entomologists at Virginia Tech, applying horticultural oil, at the rate suggested on the packaging, will remove the infestation.
Check for disease. The major disease of pears is fire blight. Symptoms to look for are leaves, blossoms and branches appearing scorched and discolored and cracked, oozing bark. To control the bacteria that causes fire blight, remove and destroy infected branches and prune several inches below any discolored tissue. If the disease is severe, you may have to remove the entire tree. If you are unsure if the tree has fire blight, take an affected branch to your county cooperative extension office for a diagnosis.