A method for developing conifer cotyledonary somatic embryos is described. The method includes culturing conifer pre-cotyledonary somatic embryos in, or on, a development medium at a temperature from about 20° C. to about 22° C. for a first incubation period sufficient in length for at least a portion of the pre-cotyledonary somatic embryos to develop into cotyledonary somatic embryos, and culturing the cotyledonary somatic embryos in, or on, the development medium at a temperature from about 10° C. to about 15° C. for a second incubation period sufficient in length for at least a portion of the cotyledonary somatic embryos to reach anatomical maturity.
