Lettuce value chain

Producers source lettuce seed across head, leaf and cos types selected for bolt resistance, tip burn tolerance and visual appeal. Pelleted seed sown into plug trays enables precision transplanting and uniform field establishment across successive plantings.

Lettuce is cultivated in open fields, hydroponic tunnels and shade net structures with weekly succession plantings for continuous supply. Light overhead irrigation, tip burn prevention through calcium management and aphid and downy mildew control are the primary production challenges.

Heads or leaves are cut in the cool morning hours and immediately placed in cold water to remove field heat. Lettuce loses one percent of its weight per hour at ambient temperature making rapid cooling the single most critical post harvest operation.

Lettuce is sorted for size and quality, packed into crates or bags and vacuum cooled to one degree celsius. Vacuum cooling is preferred over forced air for lettuce as it removes heat rapidly without causing physical damage to the fragile leaves.

Lettuce is washed, shredded and blended into bagged salad mixes for retail convenience channels. Fresh cut salad processing is a high value channel that transforms bulky whole heads into premium portioned products with strong consumer demand.

Fresh and bagged lettuce is distributed through cold chain logistics to retail stores, quick service restaurants and institutional caterers. Speed to shelf is the defining competitive factor as lettuce quality degrades visibly with each day of age.