Lettuce crops are at risk of frost damage, particularly in areas where temperatures drop below 28°F (-2°C) for extended periods. Ready-to-harvest heads and crops with unknown cold tolerance are especially vulnerable. Prolonged or repeated freezing can lead to damaged leaves, reduced quality, and potential crop loss. Gardeners should also be cautious of microclimates in their gardens, as low pockets and calm, clear nights can lead to colder conditions near the ground. Frozen leaves may become water-soaked, collapse, or turn brown, rendering them unusable.