To define a number range, you have to create a new number interval: 1  Specify an alphanumeric key with up to 2 characters. 2  Specify the limits of the number interval.  Mark the number range if it is planned for external number assignment.
Inspect the lettuce plants for leaves that are ready to harvest. Most leaves are mature enough once they reach 1 to 3 inches long, but they should still be tender up to 6 inches long. Cut off the outer leaves of the plants with a small pair of garden shears to harvest just a few leaves.
Rinse the entire head of lettuce under cool, running water, holding it cored-side up. Turn the head over and shake it to remove any excess water. Place it on a clean, dry towel or in a colander to drain.