Abstract: A method of producing Trichoderma conidia in submerged culture comprises first preparing an inoculant of a desired strain of Trichoderma. Then, the inoculum is placed in a sufficient volume of a suitable liquid medium. The medium is maintained under substantially constant illumination, agitation and aeration at a temperature from about 25.degree. C. to about 30.degree. C., and a pH from about 5.8 to about 7.0. The culture is grown from a sufficient period of time until the density of conidia is about 5.0.times.10.sup.8 per ml, and then the conidia so produced are harvested. A similar method is provided for the production of Trichoderma chlamydospores.