After Colorado’s Amendment 64 passed, making the recreational use of marijuana legal beginning on Jan. 1, 2014, the state went for almost two years without even some basic regulation of pesticides. It was a time pot growers with all sorts of pesticides would drench plants being grown over cement warehouse floors.

Amendment 64 said only the state’s Department of Revenue could regulate recreational marijuana. Edible marijuana products, as well as smokable products, are available across the state.

Finally, in November 2015, then-Gov. John W. Hickenlooper declared that Colorado marijuana products contaminated by pesticides were a threat to public safety. Hickenlooper ruled marijuana contaminated with so-called “off-label” pesticide use was a risk to public health. He ordered actions by several state agencies to “hold and destroy” any pot plants that were sprayed with such pesticides.

By the following spring, Colorado’s “wild west” era for canibus growers was ending. On March 30, 2016, the Colorado Department of Agriculture adopted rules for the cultivation of cannabis in the state. Those rules — three years into the recreational pot era — set forth limited pesticide use.

Currently, it is unlawful for anyone to store or use pesticides, or pesticide containers for growing marijuana that is inconsistent with labeling requirements in an unsafe, negligent or fraudulent manner that is inconsistent with pesticides on a specific list with approval.

The list-updated recently for 2020– and  developed by CDA “is intended to assist Colorado cannabis growers in identifying which pesticides can be used legally in accordance with the Pesticide Applicators’ Act and its Rules in the production of Cannabis (marijuana and industrial hemp), it is not an endorsement or recommendation to use these products in the production of cannabis in Colorado.”

The CDA says the products “have not been tested to determine their health effects if used on Cannabis that will be consumed and thus the health risks to consumers is unknown.” Therefore, CDA makes no assurances of their safety or effectiveness when used on cannabis and is not responsible or liable for any such use.

To view or download the current list, click on one of the below links:

• Pesticides allowed for use in Cannabis production in accordance with the PAA Rule: Effective July 2020
  • PDF
  • Excel This document may not open properly if using a program other than Microsoft Excel.

Products added since the last updat are now highlighted in red on the PDF version of the file. The Excel version has the date that each product was added and can be sorted or filtered by name, date, active ingredient, etc.

The CDA is reviewing pesticide labels upon request and maintaining a list of products whose labels are reviewed that can be used on cannabis without violating Part 17 of the PAA Rules, as long as the applicator follows the label directions.

A commercial grower in Colorado is expected to know the requirements of the Federal Pesticide Worker Protection Standard (WPS). This includes many specific requirements that producers of any agriculture commodity — including cannabis — must comply with if they have people working in an area wher plants have been treated with pesticides or who mix or apply pesticides.

Another dozen states have joined the recreational marijuana business since Colorado got it all started.  All have had to deal with pesticide use by pot growers.  From Jan. 1, 2014, to date, marijuana sales in Colorado have totaled almost $9 billion.