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How Beneficial Insects Combat Pests in Cannabis Grow Environments

Which is worse in a cannabis grow room, aphids or mites? Ask an experienced grower this question, and the reply will be they are all detrimental to marijuana plants. Whether the battle is with underground root aphid inhabitants or the microscopic russet mite populations, common cannabis pest infiltrations are extremely difficult to overcome.

Marijuana growers often turn to neem oil or chemical pesticides and insecticides to terminate the invasions. Many times though, resilient pest species build up resistances to these harsh inputs. Therefore, a continual rotation of different types of bug killers is necessary to slow the spread.  As the pesky bugs learn to adapt to multiple inputs, it seems the more you spray, the faster they reproduce.

Outdoor organic cannabis growers have help from Mother Nature to thwart bad bug infiltrations on their plants. She sends in the good bugs to help eradicate the nuisance invasion in a thriving ecosystem. If you have ever noticed a large population of ladybugs in an outdoor garden, there is probably a substantial aphid assault playing out somewhere.

Indoor growers can utilize the same tactics by incorporating beneficial insects in cannabis grow rooms to combat destructive pests. Fighting bad bugs with good ones is a natural means of commanding pest invasions.

Pesticide Treatments VS Beneficial Insects

As long as folks have been growing marijuana, they have undoubtedly battled pest infestations. The common practice when eliminating nuisance fungus gnats or destructive spider mite outbreaks in the past has utilized commercial pest control products.

Heavy-hitting insecticides and fungicides are often used to rid the nuisance bugs. Unfortunately, many of the chemical compounds found in these powerful products are toxic when inhaled or ingested.

Another drawback to pesticide sprays is the insidious nature of bugs’ ability to adapt to their environment. When the same pesticide is applied repeatedly, pest populations soon become repellent to chemical compounds. A rotation of two or three different insecticidal products is required to combat the irrepressible pests from building resistance to the sprays.

Beneficial insects reduce many of the headaches incurred from frequent foliar spraying, not to mention cost savings on pesticide products, labour spent mixing the bug spray, and application processes. When introduced into cannabis grow environments, biological control agents eliminate these hefty expenditures.

Establish an IPM for Beneficial Insects in a Grow Room

At times, it seems no matter how strict marijuana growers are with cleanliness, sterilization, and isolation in a grow room, crafty pests often just appear. Incorporating beneficial insects into integrated pest management (IPM) programs before an outbreak occurs reduces the chance for unwanted predators to multiply.

While it is impossible to determine what type of pest may infiltrate an indoor grow set-up, introducing various good bugs early in cannabis plant growth reduces the survival rate of a renegade pest species. Afterwards, similar to an IPM using pesticide spray timetables, establishing schedules for the release of biological control agents ensures the populations stay active.

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Types of Biological Control Agents for Cannabis

Entomologists have uncovered several species of beneficial insects focused on eliminating damaging pests common in cannabis cultivation. While some natural predators, such as praying mantis and assassin bugs, feed on many different types of insects, other beneficial organisms target specific families of insects.

Mite Control

The two-spotted spider mite is a common nuisance pest in cannabis cultivation. The tiny destructive mites sneakily hang out on the underside of cannabis leaves. As a result, marijuana growers will see light speckling on the tops of fan leaves as devouring spider mites suck the life out of plant cells.

Fortunately, introducing predatory mites in the grow room combats the damaging pests. For example, Phytoseiulus persimilis are bright orange and red predators with a zest for annihilating spider mite populations. They can devour up to 20 spider mites (or their eggs) each day while reproducing offspring throughout their fifty-day life cycle.

While spider mite populations are tough to control, most growers who have battled hemp russet mites and broad mites agree that they are by far more elusive. Because of their small size, less than 0.2mm, marijuana growers need magnification of 60X to see these troublesome pests.

Unless a grower has a good eye for early leaf curling and can spot fan leaves before they turn a rusty brown colour, hemp russet mite populations have already exploded. Fortunately, the Neoseiulus fallacis predatory mite introduced in early vegetative growth IPM’s will combat their arrival.

Broad mites are another culprit that can infest cannabis plants and cause substantial damage before a grower even realizes they are in the room. These microscopic pests are between 0.1 – 0.2 mm in length and produce toxic saliva that causes distortions and malformed leaf structures.

The predatory mites used to overtake broad mite infestations are Amblyseius andersoni. These helpful species also attack two-spotted spider and russet mites. Introducing these predators in a grow room helps reduce any malicious mite breakout.

Because mites are so small, it is easy for them to blow through open doors or hitch a ride on someone’s clothing. Therefore, preventative measures are much easier with these beneficial mites than eradicating the damaging pests once they have entered a grow room.

Aphids Love Cannabis

When a population of aphids ascends in a marijuana grow room, be ready for a battle. Since these pesky creatures are easy to see, you can almost watch them multiply before your eyes.

Aphids have the ability to reproduce sexually or asexually, depending on the season. Most eggs, especially in the spring and summer, are female. These girls reproduce by either laying eggs or by giving birth to live young females. Considering aphids can develop into reproductive adults within seven to eight days, it’s easy to see how their populations get out of control quickly in a grow room.

Fortunately, ladybugs love feeding on aphids. These cute little red bugs can quickly knock down aphid populations as long as there is an abundant food source to engulf.

Parasitic wasps are another option for aphid control. These brutal attackers are attracted to the sticky, sweet residue excreted from aphids onto plant surfaces. The female wasps lay their eggs inside nymph stage aphids. When the parasitoid larvae hatch, they begin devouring the aphid from the inside out, mummifying the creature. Then, as the adult matures, it simply eats its way out of the mummy and begins searching for its next meal.

Another beneficial insect that can take out aphids and other pests such as whiteflies, leaf miners, and thrips is Green lacewings. These aggressive creatures paralyze their prey with venom and then draw out their body fluids. Lacewing larvae consume 200 or more pests a week if pest populations are available.

Beneficial insects used to conquer cannabis pest problems

Conquering Substrate Dwelling Pests

Fungus Gnats and Root Aphids are two common pests associated with indoor cannabis crops. Both species love warm, moist conditions while feeding on plant root hairs, fungi, and organic materials. However, if populations of these pathogens get too high underground, cannabis plants begin showing symptoms of distress.

Fungus gnats are a nuisance, especially at watering times as they go for your face and ears. They are also hard on a cannabis plant’s root system, especially in large populations. These aggravating bugs have a short lifespan between 3 – 4 weeks; however, each gnat can lay up to 300 eggs in the last seven days of adulthood.

To combat these pesky flying bugs, Rove Beetles can be released to help combat populations. These hearty predators feed on any small soil dwellers in larvae or egg stages and are voracious as adults. Rove beetles can consume over 150 fungus gnats per day in their adult stage.

Root aphids are harmful bugs that can cause damage in soil or coco substrates simply because a grower cannot see their activity. Similar to above-ground aphids, underground dwellers have piercing mouths that extract sugars from root zones. As root aphids gnaw away at delicate root systems, cannabis plant development may become stunted.

Beneficial nematodes are the go-to for underground pest prevention. These barbaric predators enter an intruding pest through body walls or other orifices. Upon entry, they infect the host with toxic bacteria, killing the intruder within 24 – 48 hours. Implementing beneficial nematodes into a routine IPM guarantees no hidden pest invasions underground.

Control Cannabis Pest Problems with Beneficial Insects

Instead of waiting for pest outbreaks to occur in a grow room, introducing beneficial predatory insects early in plant development squashes their existence. In addition, a structured IPM with designated release dates of the good bugs ensures success in cannabis cultivation.

Post author
Charle Thibodeau
Charle’ Thibodeau is a freelance writer with almost a decade´s experience, specializing in cannabis content for the past two years. A strong motivation to educate, inform, and promote the culture surrounding this miraculous plant is her earnest mission.
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