Are they moving? I ask, because it could be a fungus. For an organic solution, buy a neem-based or pyrethrum and sulphur-based insecticide, mix as directed, and drench the soil. At this time of year, the tiny bugs may be hatchlings of any of a number of species. The insecticides I've recommended have wide-based applications, to include both fungi and insects. Can you give a more detailed description of the pests or send a pic?