Common Pests of Hemp and Cannabis Plants

The cannabis industry has steadily grown over the years, and with that expansion comes a remarkably diverse set of insects that want a piece of your crop. Some studies have reported over 250 insect, mite, and mollusk species that live on cannabis. While not every species living on the plant eats cannabis, there are several of them that can cause damage and negatively affect your yields. 

Sap-sucking pests

Well-camouflaged aphids

Some of the most common pests in hemp and cannabis feed by piercing plant tissues and extracting sap. This feeding weakens plants and can spread pathogens.

Aphids – Aphids can be challenging for many cannabis growers as there are several species that can cause damage, including cotton aphids (Aphis gossypii), potato aphids (Macrosiphum euphorbiae), green peach aphids (Myzus persicae), and the cannabis aphid (Phorodon cannabis). Heavy infestations can spread viral diseases and cause sticky honeydew buildup, which encourages sooty mold growth.

Spider mite infestation

Spider mites - These tiny arachnids feed on leaf cells, producing yellow speckling and eventually bronzing or leaf drop. Under hot, dry conditions populations can explode quickly and severely damage plants. 

Thrips – These small, slender insects scrape plant tissue and feed on plant fluids. Species include western flower thrips (Frankliniella occidentalis), onion thrips (Thrips tabaci), and impatiens thrips (Echinothrips americanus). Thrips cause leaf and flower deformities. 

Hemp russett mite damage

 Mites that target cannabis

Mites are especially concerning because of their small size. You may not even notice you have an infestation until you look at the plant with a hand lens. 

Hemp russet mite – Tiny mite that causes leaf curling, bronzing, and stunted growth. 

Broad mite – These mites are extremely small and usually go unnoticed without magnification. The symptoms of their damage can often resemble nutrient deficiency or herbicide damage.

                     Chewing pests

Several chewing insects can also damage hemp and cannabis crops. They are much easier to detect than mites and can cause considerable damage if left unchecked. 

A very hungry caterpillar

Leaf miners – Leaf miners chew between the layers of the leaf in a serpentine pattern. Keep an eye out for tomato leaf miners (Liriomyza bryoniae), pea leaf miners (Liriomyza huidobrensis), and American serpentine leaf miners (Liriomyza trifolii).

Caterpillars - Hemp moth (Grapholita delineana) and the Beet armyworm (Spodoptera exigua) and other budworms feed on flower buds and developing seeds, tunneling into plant tissues and leaving behind frass and damaged buds. 

Borers - The European corn borer (Ostrinia nubilalis) or Eurasian hemp borer (Grapholita delineana) may tunnel into stems, weakening plants and disrupting nutrient flow.

Indoor vs outdoor pest pressure

The types of pests you meet often depend on the growing environment. Indoor and greenhouse hemp production tends to see higher pressure from mites, aphids, thrips, and fungus gnats. Outdoor crops are more likely to be affected by caterpillars, beetles, grasshoppers, and stink bugs. 

Because hemp is a relatively new commercial crop, growers have fewer pesticide options than growers of many other agricultural crops. That makes prevention, monitoring, and biological control especially important.

Conclusion

The best strategy for controlling damaging pests is to start early. Consistent scouting, careful monitoring of leaves and buds, and the use of beneficial insects can help prevent small pest populations from turning into serious infestations.

Luckily, ARBICO offers a wide variety of pest control solutions aimed at the cannabis market. We have everything from beneficial insects to fungicides, nutritional supplements, neem oil, fertilizers, beneficial organisms and much more to help your grow. Check out our dedicated Hemp/Cannabis page here.