how long does it take for a seedling of iceberg lettuce to mature
The leaves become bitter and the plants begin to bolt as the stem elongates into a tall bloom stalk. Leaf lettuce varieties take about 40 days from seeding to harvest while head types may take 70 days. This is another reason the head types are more of a challenge. To get more from your garden space, consider interplanting your lettuce with slower maturing crops.