As more regulated states mandate Aspergillus testing as part of the overall cannabis compliance testing, this human pathogen is top of mind for many cultivators across the nation.

A current indoor Michigan cultivator had been experiencing microbial failures related to Total Yeast & Mold (TYM) and Aspergillus, drastically cutting into their cultivation margins. Per the anonymized COAs included here, the facility struggled with a combination of microbial challenges and ultimately sought out the assistance of the Willow Customer Success and Science teams to stave off continuing failures.

Sample Received: 02/15/2023; Report Created: 02/21/2023


The cultivation team opted for a full Willow lease, recognizing the value of a science-based approach toward identifying and eliminating upstream contamination sources within their production facility.

Recommendations related to cleaning SOPs and environmental controls were implemented by the cultivation staff, resulting in decreased baseline microbial bioburden across all cultivated flower. 

After dialing in their WillowPure 360 operation with guidance from the Science team, the cultivation staff was able to control their upstream contamination and implement a proactive kill step to prevent spikes in contamination from creating ongoing compliance issues.

Outcome: Aspergillus Compliance

With WillowPure treatment utilized preemptively across all harvest batches, this cultivator was able to pass all compliance testing, Aspergillus included. In fact, the cultivation staff has seen a 100% compliance pass rate since fully implementing the WillowPure 360.

A sample COA from the same batch that failed for Aspergillus above is included below, demonstrating the reduction in microbial contaminants following a standard WillowPure treatment. Note the report date before Willow and after Willow implementation. Despite their early success, the cultivation staff remains focused on clean upstream growing practices paired with diligent sanitation and environmental SOPs.

Aspergillus Not Detected
Sample Received: 05/01/2023; Report Created: 05/04/2023

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