'Gravenstein' apples espalier trained to wall

This unusually hot summer has sped up the harvest time of your backyard apple crop. Here are five good indicators that the apples are ready to harvest.

Change in skin color is one of the easiest for gardeners to spot. The green skin pigment gradually matures to red, yellow or oft green, depending on variety. Photos in fruit nursery catalogs, many available on-line, are good resources for fruit color. Some varieties will develop red skin color before they’re fully ripened, so color should not be your only indicator of maturity. The bottom of the apple (calyx end) turns from green to light-yellow.

On some varieties fruit shape is another change. Red Delicious and many varietal sports form 4-5 nubbins (raised bumps) on the bottom. The nubbin formation is dictated by the region where the variety is grown. Red Delicious from the Northwest U.S. is most to type, while those produced in the warm southeastern states less so.

Next harvest tip is flavor. Bite into an apple and determine its taste. You may not know what kind of apple that you’re eating, but its flavor and sweetness may be what you like. Apples which are hard to bite into or have a sour or starchy flavor are not ready. The inside flesh color often changes from oft-green to white, sometimes to yellow.

The number of days (interval) from bloom period to harvest date can be a reliable guide. Extremely hot summer weather may move up the harvest interval by 7 to 10 days. The approximate picking intervals of popular varieties are: Gala and McIntosh @ 110-115; Empire, Jonagold, and Jonathan @135-140; Red Delicious and Golden Delicious @ 145-150; and Rome, Granny Smith, and Winesap @155-160 days.

Finally, if you harvest too early, apples will be of smaller size, but will ripen off the tree indoors.