S.R. Simmons, E.A. Oelke, P.M. Anderson
Wheat ( Triticum aestivum L. ) can be classified as winter or spring growth habit based on flowering responses to cold temperatures. Winter wheat development is promoted by exposure of the seedlings to temperatures in the 38 degrees to 46 degrees F (3 degrees to 8 degrees C) range. Such types are usually planted in the fall which exposes the seedlings to cold temperatures during late fall and winter. Spring-types, however, do not require exposure to cold temperatures for normal development and can be planted in spring. Both winter- and spring-types, when properly grown in Minnesota, head in the late spring or early summer and mature by mid- to late-summer.
The description of wheat development provided here applies mostly to spring wheat, although the basic development patterns for all cereals are similar. Figure 1 shows major developmental stages in spring wheat and approximate time intervals between them in Minnesota. A difference in maturity may exist among varieties or between seasons.