Like the Liberty apple, Asian pears show great promise for Maryland homeowners who want to grow backyard fruit with a minimum of pesticides.
Familiar varieties of pears -- like Bartlett and Bosc -- require fewer applications of pesticides than do most apples, said Dr. Christopher S. Walsh, fruits specialist for the Cooperative Extension Service University of Maryland System.
But Asian pears require even less spraying. Since their attractive, ornamental foliage is not subject to disease pressures, no spraying is required until the trees start bearing.
Asian pears are roundlike an apple, said Walsh. They also have the firmness and crunchiness of an apple, but they taste like a conventional pear. And they canbe allowed to ripen on the tree. By contrast, conventional pears must be picked when green and kept in cold storage for four weeks to achieve the best flavor.
According to Walsh, the Asian pears grown inthis country come from Japanese, Chinese and Korean parentage, so they are a mixture of various species. Chinese varieties appear to be the most resistant to fire blight. Japanese pears are tolerant to fireblight, but their degree of resistance is not fully known.
Asian pears cross-pollinate readily with the Bradford ornamental pear, Walsh said. And they have a comparable hardiness range. Since Bradford pears seem to be growing everywhere these days, you probably don't needa second fruiting pear to pollinate your Asian pear tree.
Walsh said that pears generally prosper in heavy clay soil -- which is plentiful in much of Maryland -- better than do peaches and apples. Pears are more suited to warm areas than are apples; their hardiness range is comparable to that for peaches.
April is the best month for planting pear trees in Maryland. If you live east of Interstate 95, you also will find November a good month to plant.
Asian pears can be purchased either as dwarf or standard trees. But Walsh recommends buying standard trees and limiting their height to 10 or 15 feet by annual pruning. This eliminates the need for a ladder when picking fruit. Without annual pruning, Asian pears will grow large like a mature Bradford ornamental pear tree.
"Standard Asian pear trees will produce larger fruit than a dwarf tree," said Walsh. "And they probably will have a longer life." He also said that commercial growers use only standard pear trees. Dwarfing rootstocks are not recommended exceptfor apples.
Keep pear trees tied to a single stake during the first year after planting. Plant them about one inch deeper than they were growing in a nursery. Be sure that the graft mark is above ground.If trees are planted too deep, their roots can die for lack of oxygen.
After the soil settles, fill in the basin around your pear treebefore the ground freezes. This can keep your tree from standing in a wet hole all winter.
Pear trees are vigorous, so you don't need to mulch or cultivate around them once they are established. They make good lawn trees. Feel free to mow right up to them. Norman lawn fertilization should be adequate for pear trees. If they're growing 24 to 36 inches a year, they're doing fine.