Sleaford is a town within the North Kesteven district of Lincolnshire, England. It is thirteen miles (21 km) northeast of Grantham and seventeen miles (27 km) northwest of Boston, and has a total resident population of around 15,000.Until recently, Sleaford, which takes its name from the River Slea, was primarily an agricultural town, supporting a cattle market and famous seed companies such as Hubbard and Phillips and Sharpes International Seeds (whose history can be traced from their merger with Zeneca Seeds in 1996, which formed Advanta Seeds, right back to 1560). Today however Sleaford is developing as a tourist and craft destination.