Cannabis Cultivation and Science Podcast

Episode 162: Dips, Sprays, & Phytotoxicity: Mastering Oils in Cannabis Cultivation with Julie Graesch

Cannabis Cultivation and Science Podcast

Show Notes

In this episode, Tad Hussey welcomes back Julie Graesch, Technical Services Manager at BioWorks, to demystify one of the most common yet misunderstood tools in a grower’s IPM toolkit: Horticultural and Essential Oils.

While many growers reach for oils to "suffocate" pests, the science behind their efficacy—and the risks of phytotoxicity—is far more complex. Julie breaks down the critical differences between EPA-registered mineral oils and 25B essential oil products, explaining how different modes of action like desiccation, paralysis, and behavioral repellency work together to bypass pest resistance. They also dive into the "why" behind professional formulations, discussing how emulsifiers and surfactants make the difference between a clean kill and a scorched crop.

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