Twentieth Centery is an Asian pear that bears crisp, juicy fruit that has some tartness, especially near the core.
Fertilize annually, using a split application. Apply a half to a third cup of 10-10-10 fertilizer per year of tree age with a maximum application of 8 cups per tree. Half of the amount should be applied before growth begins and the other after fruit set. Broadcast each application over an area that corresponds with the drip line of the tree. If fruit set is poor, do not apply the second half of the application. Too much nitrogen may encourage shoot infection by fire blight.
Heavily pruned trees most likely will not need fertilizer for a year or two. Asian pears are often hand-thinned twice during the early growing season. The home grower may choose to thin only once. This should be done 14 to 40 days after petal fall. One fruitlet should be left on every other spur cluster or about 6 inches between fruits.
Heavy fruit thinning is essential to encourage large fruit and prevent limb breakage. This should be done within six to eight weeks after flowering when the fruit is dime-sized. Avoid excess nitrogen fertilization to help reduce fireblight Prune infected branches 18 inches below the affected area and burn or bury all infected material. Clean pruning tools between cuts with a dilute solution of household bleach (one part bleach to nine parts water).