What is an example of a planting date adjustment to avoid damping-off in lettuce?

Choosing to wait until warmer temperatures to plant is a strategy used to avoid damping-off in lettuce. Damping-off is primarily caused by soil-borne pathogens that thrive in cool, damp conditions prevalent in early spring. By delaying planting until temperatures rise, the microbial activity that leads to damping-off decreases, as many pathogens associated with this disease prefer cooler conditions. Warmer soil temperatures are more conducive to healthy seedling growth and can foster a competitive environment that may deter the growth of harmful fungi and pathogens.

The other options do not effectively address the issue of damping-off. Planting earlier in the spring can increase the risk of disease due to cooler temperatures and moisture that favor pathogenic fungi. Planting mid-summer may help avoid certain fall diseases, but it does not specifically target the damping-off problem that occurs in cooler months. Lastly, using greenhouse methods can certainly promote earlier growth and may have benefits in terms of disease management, but without the specific consideration of soil temperature and moisture conditions, it does not directly address the risk of damping-off that is associated with cooler outdoor planting conditions.