Hemp is a robust plant. It grows in a variety of conditions, doesn’t need a ton of water, and resists a lot of pests. However, hemp isn’t immune to foreign invaders. While there are a lot of pests partial to hemp, it’s only a small percentage that can actually wreak havoc on a crop.

The top offenders

How pests attack hemp, and what kind of lasting damage they can do to the plant is different with every visitor. Understanding how each can impact a crop can help you react quickly and get rid of these pests before they have time to do severe damage.

Spider mites

While very obviously pests, spider mites actually fit into the arachnid family. They’re not insects, but they’re very tiny. They also tend to live on the underside of leaves so they’re hard to detect. The best telltale sign of spider mites, isn’t the mite itself, but rather the small webs you’ll find on your hemp plants. 

WIth an appetite for chlorophyll, spider mites damage hemp plants by preventing them from carrying out photosynthesis. Mama spider mites can lay thousands of eggs, all of which hatch within a few days. It doesn’t take long to have an infestation on your hands.

Spraying down your hemp crop with water will help dislodge existing spider mites, but it won’t ensure they’re gone for good. Follow this treatment up with an application of neem oil at seven-day intervals. You can also reduce infestation by separating the infected plants from those that are still healthy. If you can do this, make sure no leaves are touching between plants.

Thrips

Thrips like the sap of hemp plants, and steal it from buds and new leaves. They’re tiny, winged insects that leave behind what’s known as a stippling injury where they feed. To us, it looks like a small area that’s lighter in color. This makes them hard to detect.

When thrip infestations hit high numbers, you’ll begin to see extensive leaf scarring and leaf distortion. This is rare for outdoor crops though, since nature helps deter the insects from your hemp plants. You don’t want to let them enjoy their meal though, since thrips are also known to carry plant viruses. 

Regular pruning can keep thrips at bay. Target areas where you can see injuries to the plant.

Cannabis aphid

Light in color, cannabis aphids begin a cream color that eventually changes to light green, pale pink, and light brown. They can have wings, but don’t always.

Cannabis aphids like to hide on the underside of hemp leaves. From there, they suck nutrients right out of the plant. This activity doesn’t create any exterior damage, but instead it’s the loss of fluids that harms the plant. The insect does clue you in to their presence though by leaving behind a sticky fluid called honeydew. This appears as small, shiny spots on the plant.

Their rapid reproduction rate can make them particularly damaging to a hemp crop. Their fluid sucking can lead to slowed growth, wilting, and leaf yellowing.

Checking your plants regularly can help to catch the presence of aphids before a full-on infestation occurs. To quickly get them off plants, blast them with a power sprayer and water. You can also prune leaves and buds that look heavily infected.

Budworms

The real pest in this situation is the white moth. They lay their eggs on hemp plants, and budworms are what hatch. They’re easy to miss since they’re green and only come out at night.

Budworms are pests because they like to chew hemp flower and hemp stems. They’ll wiggle their way into hemp buds and slowly eat them from the inside. You’ll know they’re at work if your flowers don’t open at all or look raggedy.

While they only eat for about a month, before moving on to the next stage in their lifecycle, that’s enough time to damage the most lucrative part of your hemp crop. You can get rid of them by removing buds that have noticeable holes bored in them already, but the best defense is to get them while they’re still eggs.

Fungus gnats

Small and mighty, fungus gnats are only a few millimeters long. They look like black flies with long legs, popping up mostly in winter and spring.

Fungus gnats start feeding on fungus within the soil, but once that meal is over, they start attacking the root hairs of your hemp plants. This makes the plants more susceptible to fungal disease. It can also cause abnormal growth and leaf color. Even in their larval stage as root maggots, fungus gnats eat the roots of your hemp plant.

To check for fungus gnats, look within the top 2-3 inches of soil. If you find them, a good way to get rid of them is to let the soil dry out for a bit. Turn off any watering system you’ve got on auto-water, and cross your fingers it doesn’t rain. You can also spray the soil with a liquid dish soap and water mixture.

Hemp flea beetles

Some of these beetles like leaves, while others go for roots. Either way they’re out to do damage. Even though species vary, all hemp flea beetles are pretty small with larger hind legs so they can jump.

A quickly-multiplying insect, hemp flea beetles are dangerous for seedlings and young hemp plants. With the right numbers, they can even kill. You’ll notice they’re around, even if you don’t see little black dots, by the holes they leave behind.

Dusting your crop with talcum powder can help repel this unwanted pest, or you can use sticky traps to capture the beetles as they jump.

How hemp protects itself

Hemp isn’t defenseless when it comes to warding off pests. The plant actually produces chemicals that repel unwanted guests. Certain pure cannabinoids may even inhibit or kill bacteria, fungi, and insects. This bodes well for the overall resiliency of your hemp crop.

Preparing for the unknown of hemp farming

Growing any crop is never guaranteed successful until harvest and processing are complete. The same goes with hemp, although Arbor Vita8 does everything they can to reduce your risk as a hemp farmer. It all starts with genetics, and our experienced staff can help you find the perfect plant for your environment. From there we support you with resources and services all the way through to the final sale of your crop’s products. We only offer the best in equipment and processing practices. Contact us today to learn more.