Trends in lettuce and spinach production in the United States

Authors: Simko, Ivan; Mou, Beiquan; Richardson, Kelley; McCreight, James - Jim

Submitted to: Eucarpia Conference on Lettuce and Leafy Vegetables
Publication Type: Abstract Only
Publication Acceptance Date: 4/1/2019
Publication Date: 6/25/2019
Citation: Simko, I., Mou, B., Richardson, K.L., McCreight, J.D. 2019. Trends in lettuce and spinach production in the United States. EUCARPIA Leafy Vegetables International Conference, June 24-28, 2019, Olomouc, Czech Republic.

Interpretive Summary:

Technical Abstract: Lettuce (Lactuca sativa L.) and spinach (Spinacia oleracea L.) production in the United States is concentrated mostly in California and Arizona, where both leafy vegetables are grown year-round. Lettuce cultivars are divided into eight horticultural types on the basis of the shape and size of the head; the shape, size, and texture of leaves; stem length; and seed size. U.S. lettuce products are categorized into three market uses: whole heads, bulk harvest (for salad processing, food service, or value-added products), and baby leaf or spring mix. The three main lettuce types produced in the United States are iceberg, romaine, and leaf. Yields of all lettuce types continue to increase. For example, in California from 1992 through 2017, summer production yield of iceberg increased 32% in Salinas Valley, and winter production yield of iceberg in Imperial Valley increased 71%. During this same period, yield of romaine and leaf types increased 28% in Salinas Valley but remained essentially unchanged in Imperial Valley. Area planted to iceberg decreased 40% and romaine increased 500% from 1992 to 2017 in Salinas Valley, and similar trends have occurred in the winter production areas of California and Arizona. The U.S. is the 2nd largest spinach producer in the world, with more than 26,000 ha planted and 330,000 metric tons harvested annually, with a worth of $423M. About 85% of the crop is produced in California and Arizona. Spinach yield has steadily increased over the years, largely due to the use of disease-resistant hybrid cultivars and high seeding rates on wide beds. A new downy mildew race appears every 20 months, on average. It is especially challenging for organic spinach growers without effective organic fungicides. At least 40% of the area planted to spinach in California is organic. Spinach is mostly consumed as bagged salad in the United States. Fresh spinach consumption in the U.S. has not fully recovered from the Escherichia coli outbreak in 2006, now at 0.7 kg per person annually. Per capita spinach use in the U.S. is highest among Asians and women 40 years and older.