Abstract: The embodiments disclose a method of determining terpene-based biocontrol agents for cannabis and hemp plants including placing terpene isolates-soaked discs in a pattern onto the bacterial inoculated plates in duplicates with a diluent-soaked negative control disc in the center, testing and evaluating combinations of bioactive terpene isolates identified under specific aims for synergy, wherein the specific aims are to evaluate individual terpenes for effectiveness in controlling common fungal and bacterial populations found on indoor and outdoor grown cannabis plants, developing terpene isolates formulations and retest under the specific aims to ensure that added ingredients do not interfere or dampen bioactivity, testing terpene isolates formulations on cannabis and hemp seedlings, harvested cannabis and hemp flowers and cured cannabis and hemp flower for suitability, and testing terpene isolates formulations in challenge experiments on cannabis and hemp seedlings.