Sod is grown on specialist farms. For 2009, the United States Department of Agriculture reported 1,412 farms had 368,188 acres of sod in production.
It is usually grown locally (within 100 miles of the target market)to minimize both the cost of transport and also the risk of damage to the product. The farms that produce this grass may have many varieties of grass grown in one location to best suit the consumer's use and preference of appearance.
It is usually harvested 10 to 18 months after planting, depending on the growing climate. On the farm it undergoes fertilization, frequent watering, frequent mowing and subsequent vacuuming to remove the clippings. It is harvested using specialized equipment, precision cut to standardized sizes. Sod is typically harvested in small square slabs, rolled rectangles, or large 4-foot-wide (1.2 m) rolls.
Mississippi State University has developed a hydroponic method of cultivating sod. For the very few sod farms that export turf internationally, this soil-less sod may travel both lighter and better than does traditional sod when shipped. Additionally, since the sod is not grown in soil, it doesn't need to be washed clean of soil down to the bare roots (or sprigs), and time to export is shortened.
Sod has two main utilities: immediacy, and cultivar availability.
Immediacy
In many applications, such as erosion control and athletic fields, immediacy is a key factor. Seed may be blown about by the wind, eaten by birds, or fail because of drought. It takes some weeks to form a visually appealing lawn and further time before it is robust enough for use. Turf largely avoids these problems, and with proper care, newly laid sod is usually fully functional within 30 days of installation and its root system is comparable to that of a seeding lawn two or three years older. Sod reduces erosion by stabilizing the soil.
Cultivar availability
Many prized cultivars (such as Bella Bluegrass) only reproduce vegetatively, not sexually (via seed). Sod cultivation is the only means of producing additional plants. To grow these varieties for sale, turf farms use a technique called sprigging, where recently harvested sod mats are cut into slender rows and replanted in the field.
