Blueberry picking guide

Iowa State Extension lists three signs of a fully ripe blueberry: it is uniformly blue, it tastes good, and it separates easily from the plant. It warns against picking on color alone, because a berry is often blue for some time before it is fully ripe.

Cornell Cooperative Extension’s Lake Ontario Fruit Program says letting berries hang 3 to 5 days after they turn blue improves both flavor and size. Unripe berries will still turn blue after picking, but they stay smaller and lower in sugar than berries ripened on the bush. Utah State Extension adds that blueberries do not ripen after picking and that ripe ones are dark blue with a powdery bloom; skip reddish or wrinkled berries.

Cultivated highbush blueberries do not ripen evenly within a cluster, Cornell notes, although ripening becomes more even as the season goes on.

Cornell’s technique: roll ripe berries from the cluster into the palm of your hand with your thumb, rather than plucking them one by one as you would most fruit. Fully ripe berries separate easily from the plant (Iowa State). Finger pressure can damage berries, Cornell notes, so handle them gently.

Cornell also advises against picking berries when they are wet, and notes that berries picked early in the day, before heat builds up, keep longer.

Call the farm or check its website for picking conditions; the Massachusetts Department of Agricultural Resources notes that crop availability varies with the weather each year. Pint containers are the traditional blueberry size, Cornell notes; ask whether the farm sells by the pint, the quart or the pound, and whether you may bring your own container.

For food safety, N.C. Cooperative Extension’s messages for U-pick customers apply here too: wash your hands before picking, use clean containers, and do not eat, drink or smoke in the field.

Typical months published by state agriculture departments and Extension services. The season moves with the weather, so check with the farm.

Refrigerate them right away, Iowa State Extension says. Utah State Extension’s method: remove moldy or damaged berries, then refrigerate the rest unwashed and loosely covered with paper towels. Clean them only when you are about to use them, by rolling them on a towel or rinsing them gently without soaking, then blotting dry.

Storage estimates vary: Iowa State gives a maximum of seven to ten days, Utah State says to use them within two weeks, and Cornell notes that U-pick customers typically refrigerate their berries and eat them within two to three days.

To freeze, Utah State suggests spreading washed, well-drained berries in a single layer on a lined baking sheet until firm, then packing them into freezer bags or containers.