Harvesting late summer and fall fruit

Any gardener fortunate enough to have fruit trees will be thinking about harvest by now. As always, the horticulturists at Iowa State have good advice about harvesting and storing the bounty.

Stone fruits ? apricots, peaches, and plums ? tip their readiness for harvest most clearly by a slight softening. Apricots also will achieve their characteristic color, while ripe plums will have darkened. For peaches, color is not a very reliable indicator, so these fruits do need to be checked by touch, but always with care as they are susceptible to bruising.

Once stone fruits are harvested, they should be stored at very cool temperatures ? just above freezing ? and at high humidity. Plums and peaches will keep under these conditions for up to three weeks, while apricots have a storage life of only one to two weeks.

Another popular fall fruit, the pear, benefits from well-timed harvesting and can be kept in storage considerably longer. The European pears, which are most common in Iowa, should not be allowed to ripen on the tree. As they ripen, stone cells develop in the fruits and cause a gritty texture.

Rather, pick European pears when the color changes from deep green to a yellowish green and the small surface spots change from white to brown. These fruits will be firm. They can be ripened at room temperature. Ripening can be accelerated by placing the pears in a paper bag and closing it tightly. For longer storage ? up to three months ? keep the pears just a little above freezing and remove them one week before use.

Apples, of course, are a very popular tree fruit. Harvest time for these depends on the variety as well as the weather conditions during a particular growing season. Apples ready for harvest are firm, crisp and juicy and will have appropriate color and flavor for their variety. Do not use color alone as the determinant for harvest time, but rather combine the indicators, which does mean sampling an apple for texture and taste.

Sort apples carefully to set aside and use promptly those that are bruised or otherwise damaged. Small apples keep better than large ones, so use the larger ones more quickly. For long-term storage, apples like to be close to 32 degrees Fahrenheit, with humidity over 90 percent. Significantly higher temperatures lead to more rapid spoilage, while significantly lower humidity will cause apples to dehydrate and shrivel.