Romaine lettuce is medium to large in size. The thick heads are loosely connected to a central blanched base and the leaves, averaging 10-15 centimetres in length, are broad with many folds and creases. The outer leaves are dark green with a prominent white central rib, and as the leaves grow smaller in the centre, they become paler in colour almost fading to white. Romaine lettuce is crisp, succulent, and crunchy with a mild, slightly bitter taste. Romaine lettuce is an excellent source of dietary fibre, vitamins A, C, and K, thiamin, folate, iron, potassium, and manganese. It is also a good source of riboflavin, vitamin B6, calcium, magnesium, phosphorus, and copper.