Researchers developed an efficient two-stage fermentation process to mass-produce Beauveria bassiana PfBb, a fungus that kills defoliating moths damaging Ficus trees. The first stage grows the fungus in liquid to produce active spores, which are then transferred to solid substrates to produce hardy, long-lasting conidia. The optimized process produces high quantities of effective fungal spores that can be stored at refrigerator temperature for over a year while maintaining their pest-killing ability.