Answer: Parris Island Cos is a romaine type lettuce that is ready to harvest 68 days after planting. Since it is a romaine leaf lettuce you can harvest the outer leaves when they reach an edible size. The center of the plant will continue to grow and you can continue to harvest leaves. Or, you can wait and harvest the entire plant at one time. Don't wait too long, though. Hot weather will cause lettuce to bolt (send up a flower stalk) and at that time the leaves will become bitter.
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