Here are five of the top organic pest controls sustainably-minded and savvy cannabis cultivators use today to produce a superior cannabis crop.
Given the stringent regulation and monitoring of contaminants, cannabis producers must turn to organic pesticides to control harmful pests.
Several organic, aka natural pesticides, are very effective at controlling the insects common in cannabis production, i.e., mites, aphids, fungus gnats, and thrips.
However, you should be aware that even if a product is labeled “organic” or “natural,” it may not be approved by the agricultural and licensing agencies in your state. So be sure to check with state and local regulations before launching a pesticide program.
With that said, let’s look at some of the pesticides generally considered safe for use on cannabis plants, starting with the foundation of organic pest control: Integrated Pest Management (IPM).
Integrated Pest Management (IPM)
IPM is a term that has been floating around in horticulture for decades. It starts with proper sanitation in the greenhouse. There are nightmare stories abound of greenhouses that are filthy. When insects get out of hand, folks often turn to chemical controls to eradicate the pest and hope they can sneak by inspectors (some even try to cleanse the product of harmful chemicals after the harvest). Keeping a spotless greenhouse can, in some cases, eliminate insect infestations or at least prevent large uncontrollable outbreaks.
Constant monitoring is another useful IPM tool. Spotting insect or disease outbreaks before they can get out of hand is an excellent IPM practice. For example, if a plant is seen to have a mite infestation, it can be quickly quarantined or tossed out. Or in some cases, that area of the greenhouse can be sprayed with an organic pesticide.
Other effective IPM practices include choosing strains resistant to insects and fungus problems and making sure you purchase clones from a reputable supplier.
Organic Pesticides
If IPM practices are solidly in place, then plant-based or so-called organic pesticides should effectively control the pests that threaten your crop.
As mentioned above, check with your state department of agriculture or other licensing agency to see what has been approved for use on cannabis. For example, states like Oregon regularly update the Department of Agriculture’s approved list of products to use in cannabis production. Other indications that a pesticide is organic and safe to use on cannabis plants is if it is designated as “organic” by the USDA, EPA, or is labeled as OMRI approved.
One note of caution: just because a product is labeled organic doesn’t necessarily mean it comes without risk to the applicator or animals, including the so-called “good bugs,” such as ladybugs that can be of benefit to your pest prevention program. Be sure to read the labeling carefully to determine potential risks to the applicator and the environment.
Common Plant-Based Insecticides
- Neem Oil
Extracted from the seeds and fruit of the tropical neem tree, neem oil effectively controls many insects, including mites, and prevents fungal infections, like powdery mildew. As a result, some growers routinely spray neem and other organic pesticides on their plants before an infestation occurs. - Azadirachtin
Extracted from the seed of the neem tree, azadirachtin is an effective treatment for insects but doesn’t have the fungal protection that comes from neem oil. Nevertheless, it offers control over many insects, including mites, aphids, and thrips. - Pyrethrums
This plant-based alternative to highly toxic chemicals has been used in ornamental horticulture and gardens since it was approved in the 1950s. Pyrethrums are found in chrysanthemum plants and, when formulated into a spray, can be used to kill thrips and other insects that attack cannabis plants. However, the synthetic version of pyrethrums, called pyrethrins, are usually shunned by cannabis growers because it persists in the environment, and thus your plants, longer than does pyrethrum. - Bacillus Thurengensis ( BT)
BT became popular in the 1960s when it was used to kill the larvae of the gypsy moth. BT is effective at controlling insects in the larval stage. In cannabis production, it is most effective in controlling fungus gnats. Other strains of bacillus are worth looking into for the natural control of pests. - Beneficial Nematodes
A sterile potting mix like Riococo’s coco coir should be sufficient to ward off soil-born pests like fungus gnats. However, if you have pests in your soil, another chemical alternative to consider is beneficial nematodes. These microscopic critters occur naturally in the soil to maintain soil health and can be added to the soil or potting mix should the need arise.Suppose a cannabis operation includes IPM as part of its standard operating procedures (SOP) and treats insect infestations with some products listed above. In that case, there should be no need to reach for the chemicals that can contaminate your crop, harm your employees, and poison the environment. And in most states, it’s not just good practice; it’s the law.