The most common pests that can attack your marijuana plant

  • They are easy to identify once in action. From the fly mite to its ‘white fly’ sister, or others like the louse or caterpillar, these insects act quickly on the vegetation of cannabis and do a great deal of damage.
  • Fortunately, if caught in time, there is always a remedy: predators like the ladybird or craft insecticides are possible solutions. Today we will talk about pests that will drive you crazy for a while and how to deal with them.

White fly, caterpillar, louse … If you are a cannabis grower you have probably heard of these insects more than once, and not exactly in a good way. There are many plagues that endanger marijuana crops. To deal with them, the best thing is to prevent them, pay attention to the symptoms and above all, to know how to eradicate them in time. With the advice we will give you today, you can easily recognize them all and manage them to the fullest.

Fly miner

Perhaps it is the most selective parasite, since it does not attack all varieties of marijuana in the same way. About two weeks after laying the eggs inside the leaves, the larvae begin to dig tunnels; it is the first clear warning that we must begin to fight them.

Symptoms

A species of brown line that can be seen on the leaves when the larvae are making their particular tunnels or mines, eating the plant material they find in their path. You can also find small perforations made from adult flies.

Treatment

It is unlikely that this insect appears in indoor cultivation, even if the leaf is not damaged we can follow the path and remove the larva with the nails (it is ‘trapped’ inside the leaf). Outside we can opt for insecticides like Spinosad, which must be used carefully and only if there are no neighboring bees. To eliminate the adult specimens, which can continue to deposit eggs, there is nothing better than an adhesive tape for the whole cultivation, so as to make them stick together.

Red spider

This small insect, which usually presents with humidity in indoor crops, sucks the sap of the leaves and puts an end to the marijuana plant in a short time: an adult spider can get to bite a million times in less than a month. If more spiders come together, in one night they can make an entire plantation die.

Symptoms

The white spots on the leaves are the sign left by the spider while sucking the sap. It is also possible to see other black or yellow spots on both sides. Sometimes they are not noticed and at other times they are confused with the lack of nutrients. Some think they are other spots when in reality they are the same spiders, which measure just a few millimeters and have a color ranging from brown to red / orange; for this it is better to have a magnifying glass in hand. It can also happen that they leave a kind of canvas on the leaves.

Treatment

The space must be clean and ventilated. The red spider grows in dry environments and reproduces very quickly if it is over 27 degrees. So keep an adequate temperature that does not exceed 25 degrees and a relative humidity of 55-60%. Once the affected leaves or plants have been identified, they can be washed with a mixture of alcohol and water, applied with a nebulizer, and in which the water is at least 40% so as not to damage the leaves. There are several products on the market to fight the red spider. Neem oil, potassium soap or pyrethrum oil are excellent options. Another possibility is the Ecotenona insecticide, of which 2 ml are diluted for every liter of water: it is applied on the leaves to penetrate the nervous system of the spider while it nourishes itself. If you have doubts about the possibility that eggs or adult specimens have resisted the product, you need to use a different one.

Caterpillars

The caterpillars need vegetation to form the chrysalis and therefore they can ruin our plantation before the rooster crows, because they are very fast when it comes to eating. And so when the caterpillar has settled into your marijuana it is important to act as soon as possible.

Symptoms

If you see on the leaves very small yellow or translucent-looking eggs (especially in the back) or a kind of tiny black droppings, be frightened, as these are two of the clearest symptoms. But so are the teeth marks on the leaves. It is also possible to find rotten sprouts: the caterpillar is able to penetrate them.

Treatment

Once discovered, the caterpillars can be removed by hand. The ideal is to combine this action with an insecticide produced with an infusion of pepper and garlic. Another possibility is to introduce the wasps of the Trichogramma species (widely used to combat parasites) or the ‘Podisus maculiventris’, or even a biological treatment with ‘Bacillus thuringiensis’. When the plant begins to dry, it must be placed upside down to make sure that no residues remain, because the chrysalises could remain inside and repeat their attack in the next cultivation.

Trip

  • They are easy to identify once in action. From the fly mite to its ‘white fly’ sister, or others like the louse or caterpillar, these insects act quickly on the vegetation of cannabis and do a great deal of damage.
  • Fortunately, if caught in time, there is always a remedy: predators like the ladybird or craft insecticides are possible solutions. Today we will talk about pests that will drive you crazy for a while and how to deal with them.
common parasites planta marijuana
White fly, caterpillar, louse … If you are a cannabis grower you have probably heard of these insects more than once, and not exactly in a good way. There are many plagues that endanger marijuana crops. To deal with them, the best thing is to prevent them, pay attention to the symptoms and above all, to know how to eradicate them in time. With the advice we will give you today, you can easily recognize them all and manage them to the fullest.

Fly miner

Perhaps it is the most selective parasite, since it does not attack all varieties of marijuana in the same way. About two weeks after laying the eggs inside the leaves, the larvae begin to dig tunnels; it is the first clear warning that we must begin to fight them.

Symptoms

A species of brown line that can be seen on the leaves when the larvae are making their particular tunnels or mines, eating the plant material they find in their path. You can also find small perforations made from adult flies.

Treatment

It is unlikely that this insect appears in indoor cultivation, even if the leaf is not damaged we can follow the path and remove the larva with the nails (it is ‘trapped’ inside the leaf). Outside we can opt for insecticides like Spinosad, which must be used carefully and only if there are no neighboring bees. To eliminate the adult specimens, which can continue to deposit eggs, there is nothing better than an adhesive tape for the whole cultivation, so as to make them stick together.

Red spider

This small insect, which usually presents with humidity in indoor crops, sucks the sap of the leaves and puts an end to the marijuana plant in a short time: an adult spider can get to bite a million times in less than a month. If more spiders come together, in one night they can make an entire plantation die.

Symptoms

The white spots on the leaves are the sign left by the spider while sucking the sap. It is also possible to see other black or yellow spots on both sides. Sometimes they are not noticed and at other times they are confused with the lack of nutrients. Some think they are other spots when in reality they are the same spiders, which measure just a few millimeters and have a color ranging from brown to red / orange; for this it is better to have a magnifying glass in hand. It can also happen that they leave a kind of canvas on the leaves.

Treatment

The space must be clean and ventilated. The red spider grows in dry environments and reproduces very quickly if it is over 27 degrees. So keep an adequate temperature that does not exceed 25 degrees and a relative humidity of 55-60%. Once the affected leaves or plants have been identified, they can be washed with a mixture of alcohol and water, applied with a nebulizer, and in which the water is at least 40% so as not to damage the leaves. There are several products on the market to fight the red spider. Neem oil, potassium soap or pyrethrum oil are excellent options. Another possibility is the Ecotenona insecticide, of which 2 ml are diluted for every liter of water: it is applied on the leaves to penetrate the nervous system of the spider while it nourishes itself. If you have doubts about the possibility that eggs or adult specimens have resisted the product, you need to use a different one.

Caterpillars

The caterpillars need vegetation to form the chrysalis and therefore they can ruin our plantation before the rooster crows, because they are very fast when it comes to eating. And so when the caterpillar has settled into your marijuana it is important to act as soon as possible.

Symptoms

If you see on the leaves very small yellow or translucent-looking eggs (especially in the back) or a kind of tiny black droppings, be frightened, as these are two of the clearest symptoms. But so are the teeth marks on the leaves. It is also possible to find rotten sprouts: the caterpillar is able to penetrate them.

Treatment

Once discovered, the caterpillars can be removed by hand. The ideal is to combine this action with an insecticide produced with an infusion of pepper and garlic. Another possibility is to introduce the wasps of the Trichogramma species (widely used to combat parasites) or the ‘Podisus maculiventris’, or even a biological treatment with ‘Bacillus thuringiensis’. When the plant begins to dry, it must be placed upside down to make sure that no residues remain, because the chrysalises could remain inside and repeat their attack in the next cultivation.

Trip

Un vero rompicapo, soprattutto se le piante provengono da talee. This tiny insect makes very rapid movements and therefore it is necessary to act quickly to prevent it from causing much damage. Sometimes spraying Neem oil or potassium soap can help prevent it, but if it is already in the plant, you must immediately get to work.

Symptoms

Spreading yellow sticky strips along the cultivation is a good way to know if there is a trip parasite, since surely some insect will remain attached to it. You can also find out if you see silver marks on the surface of the leaves, sometimes accompanied by dots, which are the droppings. Another indicative element is the broken leaves, due to the activity of the trip that sucks the chlorophyll to exhaustion.

Treatment

Even in this case, spraying Neem oil or potassium soap will be very useful to eliminate the sore, but only if the flowering process has not yet begun. In the case where it started it is better to include predators, such as wasps and orius. These species will not be affected by the fungus ‘Verticillium lecanii’ which usually contains biological products for the fight against the trip, and therefore it is possible to combine both elements.

Mosca bianca

La mosca bianca è un esemplare conosciuto dai coltivatori di cannabis e succhia la linfa delle foglie fino a debilitare la pianta. It is very common, but it is not the most lethal.

Symptoms

The first symptom is very clear: if you shake the plants and see flies fly, they are the white ones. You can also see yellowed leaves due to the chlorosis caused by the suction of the sap, the molasses that these insects secrete or even a whitish powder on the back.

Treatment

Once the parasite has been discovered (there are prevention techniques, for example planting bollards such as basil), it is possible to introduce the ‘Encarsia formosa’ wasp or the ‘Macrolophus caliginosus’ (a species of bug). Another option is to attract flies with yellow stripes or spray Neem oil or potassium soap; these solutions must be released every five or six days until the fly disappears.

Louse

Another very rapid parasite, both when it reproduces (from 30 to 100 larvae a day) and when it jumps from one plant to another. Like the red spider it feeds on the sap of the leaves. More present in the spring, we will have to play on time once identified.

Symptoms

Yellow and dry leaves, colonies under the leaves or stems and a sort of treacle that secrete are some of the symptoms that trigger the alarm. As if that were not enough, molasses attracts ants and so if you see them you begin to suspect.

Treatment

In addition to changing when you enter the plantation site, to avoid carrying a louse from the outside, once you have discovered the pest there are several ways to go: you can eliminate them manually, crushing them, as they barely move. Predators can also be inserted as chrysopid larvae, which feed on them; put twenty of them per plant and repeat the action every month. Another option is the parasitoid wasps, the ladybirds (for outdoor cultivation) or the ‘Verticillium lecanii’ mushroom. Finally it is possible to spray on the pyrethrum plants two or three times, with pauses ranging from five to ten days. Absurdly, the excess of fertilizers can cause the appearance of the louse, so we must use them carefully. It is also necessary to control the climate, since a dry environment will help its propagation. Also, when you notice decaying leaves, you need to remove them.

Cocciniglia

  • Sono facili da identificare una volta entrati in azione. From the fly mite to its ‘white fly’ sister, or others like the louse or caterpillar, these insects act quickly on the vegetation of cannabis and do a great deal of damage.
  • Fortunately, if caught in time, there is always a remedy: predators like the ladybird or craft insecticides are possible solutions. Oggi vi parleremo dei parassiti che potranno farvi impazzire per un po’ e di come affrontarli.
parassiti comuni planta marijuana
Mosca bianca, bruco, pidocchio… Se siete coltivatori di cannabis probabilmente avrete sentito parlare più di una volta di questi insetti, e non esattamente in senso buono. There are many plagues that endanger marijuana crops. To deal with them, the best thing is to prevent them, pay attention to the symptoms and above all, to know how to eradicate them in time. With the advice we will give you today, you can easily recognize them all and manage them to the fullest.

Fly miner

Perhaps it is the most selective parasite, since it does not attack all varieties of marijuana in the same way. About two weeks after laying the eggs inside the leaves, the larvae begin to dig tunnels; it is the first clear warning that we must begin to fight them.

Symptoms

A species of brown line that can be seen on the leaves when the larvae are making their particular tunnels or mines, eating the plant material they find in their path. You can also find small perforations made from adult flies.

Treatment

It is unlikely that this insect appears in indoor cultivation, even if the leaf is not damaged we can follow the path and remove the larva with the nails (it is ‘trapped’ inside the leaf). Outside we can opt for insecticides like Spinosad, which must be used carefully and only if there are no neighboring bees. To eliminate the adult specimens, which can continue to deposit eggs, there is nothing better than an adhesive tape for the whole cultivation, so as to make them stick together.

Red spider

This small insect, which usually presents with humidity in indoor crops, sucks the sap of the leaves and puts an end to the marijuana plant in a short time: an adult spider can get to bite a million times in less than a month. If more spiders come together, in one night they can make an entire plantation die.

Symptoms

The white spots on the leaves are the sign left by the spider while sucking the sap. It is also possible to see other black or yellow spots on both sides. Sometimes they are not noticed and at other times they are confused with the lack of nutrients. Some think they are other spots when in reality they are the same spiders, which measure just a few millimeters and have a color ranging from brown to red / orange; for this it is better to have a magnifying glass in hand. It can also happen that they leave a kind of canvas on the leaves.

Treatment

The space must be clean and ventilated. The red spider grows in dry environments and reproduces very quickly if it is over 27 degrees. So keep an adequate temperature that does not exceed 25 degrees and a relative humidity of 55-60%. Once the affected leaves or plants have been identified, they can be washed with a mixture of alcohol and water, applied with a nebulizer, and in which the water is at least 40% so as not to damage the leaves. There are several products on the market to fight the red spider. Neem oil, potassium soap or pyrethrum oil are excellent options. Another possibility is the Ecotenona insecticide, of which 2 ml are diluted for every liter of water: it is applied on the leaves to penetrate the nervous system of the spider while it nourishes itself. If you have doubts about the possibility that eggs or adult specimens have resisted the product, you need to use a different one.

Caterpillars

The caterpillars need vegetation to form the chrysalis and therefore they can ruin our plantation before the rooster crows, because they are very fast when it comes to eating. And so when the caterpillar has settled into your marijuana it is important to act as soon as possible.

Symptoms

If you see on the leaves very small yellow or translucent-looking eggs (especially in the back) or a kind of tiny black droppings, be frightened, as these are two of the clearest symptoms. But so are the teeth marks on the leaves. It is also possible to find rotten sprouts: the caterpillar is able to penetrate them.

Treatment

Once discovered, the caterpillars can be removed by hand. The ideal is to combine this action with an insecticide produced with an infusion of pepper and garlic. Another possibility is to introduce the wasps of the Trichogramma species (widely used to combat parasites) or the ‘Podisus maculiventris’, or even a biological treatment with ‘Bacillus thuringiensis’. When the plant begins to dry, it must be placed upside down to make sure that no residues remain, because the chrysalises could remain inside and repeat their attack in the next cultivation.

Trip

A real headache, especially if the plants come from cuttings. This tiny insect makes very rapid movements and therefore it is necessary to act quickly to prevent it from causing much damage. Sometimes spraying Neem oil or potassium soap can help prevent it, but if it is already in the plant, you must immediately get to work.

Symptoms

Spreading yellow sticky strips along the cultivation is a good way to know if there is a trip parasite, since surely some insect will remain attached to it. You can also find out if you see silver marks on the surface of the leaves, sometimes accompanied by dots, which are the droppings. Another indicative element is the broken leaves, due to the activity of the trip that sucks the chlorophyll to exhaustion.

Treatment

Even in this case, spraying Neem oil or potassium soap will be very useful to eliminate the sore, but only if the flowering process has not yet begun. In the case where it started it is better to include predators, such as wasps and orius. These species will not be affected by the fungus ‘Verticillium lecanii’ which usually contains biological products for the fight against the trip, and therefore it is possible to combine both elements.

White fly

The white fly is a specimen known to cannabis growers and sucks the sap of the leaves to debilitate the plant. It is very common, but it is not the most lethal.

Symptoms

The first symptom is very clear: if you shake the plants and see flies fly, they are the white ones. You can also see yellowed leaves due to the chlorosis caused by the suction of the sap, the molasses that these insects secrete or even a whitish powder on the back.

Treatment

Once the parasite has been discovered (there are prevention techniques, for example planting bollards such as basil), it is possible to introduce the ‘Encarsia formosa’ wasp or the ‘Macrolophus caliginosus’ (a species of bug). Another option is to attract flies with yellow stripes or spray Neem oil or potassium soap; these solutions must be released every five or six days until the fly disappears.

Louse

Another very rapid parasite, both when it reproduces (from 30 to 100 larvae a day) and when it jumps from one plant to another. Like the red spider it feeds on the sap of the leaves. More present in the spring, we will have to play on time once identified.

Symptoms

Yellow and dry leaves, colonies under the leaves or stems and a sort of treacle that secrete are some of the symptoms that trigger the alarm. As if that were not enough, molasses attracts ants and so if you see them you begin to suspect.

Treatment

In addition to changing when you enter the plantation site, to avoid carrying a louse from the outside, once you have discovered the pest there are several ways to go: you can eliminate them manually, crushing them, as they barely move. Predators can also be inserted as chrysopid larvae, which feed on them; put twenty of them per plant and repeat the action every month. Another option is the parasitoid wasps, the ladybirds (for outdoor cultivation) or the ‘Verticillium lecanii’ mushroom. Finally it is possible to spray on the pyrethrum plants two or three times, with pauses ranging from five to ten days. Absurdly, the excess of fertilizers can cause the appearance of the louse, so we must use them carefully. It is also necessary to control the climate, since a dry environment will help its propagation. Also, when you notice decaying leaves, you need to remove them.

Cochineal

And we conclude with another parasite also known by those who do not grow cannabis: cochineal. Both inside and outside, it can act silently. And the worst thing is that they are small insects (therefore difficult to identify) and resistant to some insecticides. And if they get to the roots of the plant, the problem becomes more serious. Not to mention their droppings, which contain a fungus (the so-called fumaggine) that destroys vegetation.

Symptoms

You will recognize them by the brown or white color and a kind of white hair. They begin to appear on the stems, to then be distributed throughout the plant. If there are plants like cacti, roses or olive trees next to it, we must be very careful. As with lice, ants are another sign of their presence.

Treatment

Check the plants, both cannabis and neighboring ones, to verify the presence of the parasite. Once found, it is possible to eliminate it easily by applying a mixture with the same amount of water and alcohol by means of cotton tufts. In case some parts of the plant are very damaged, the best thing will be to remove them.

Substrate midge

This insect, whose scientific name is Sciaridae (scarves), is known as a substrate fly, a black fly or a soil fly. It has a size of about 4-5 mm and during its life cycle it passes through different phases: when it is a larva it lives in the substratum, after the metamorphosis it emerges from the surface and turns into a winged gnat.

Symptoms

This insect prefers wet environments and tends to be based on plants, and this is where you need to look for it. These are the signs that indicate whether your cannabis plants have been infected by the substrate fly:

  • Observe if some individuals become trapped on the insect-catching strips (they are yellow adhesive tapes to be placed in your cultivation).
  • Another of the first symptoms, besides being the most obvious, is that you will be able to see some of them flying close to the plants

Treatment

If this parasite is already installed in your marijuana cultivation, these are some remedies that can help you eliminate it.

  • Products that contain B.thuringiensis (Bt) or Bacilus thurgiensis Israelensis (Bti), which are bacteria that live in the soil and are used as a biological alternative to conventional pesticides
  • Neem flour: very effective against pests that develop in the substrate.
  • Enter predatory species in the substrate: Hypoaspis geolalepumites and the nematode Steinernema feltiae

Nematodes

The nematodes are commonly known as round worms due to the shape of their body. Of the 25,000 registered species, 50% acts as a parasite in plants, insects or other animals. Although there are some species of nematodes that can benefit your marijuana plants, there are other “villains” that mercilessly attack your plants even bringing them to death.

Symptoms

  • Growth slowdown
  • Chlorosis of the leaves
  • Absence of vigor due to the absence of fluids the plant rots

Treatment

  • Cleaning: change the substrate for a new and sterilized one
  • Apply effective products against nematodes such as Laotta or Skunk Neem.
  • Products with Neem oil mixed with substrate can help you fight nematodes.
  • Trichonema Prot-L, an organic product effective against this scourge that also helps to sprout plants and reactivate the soil.

Slugs and snails

Snails and slugs have a viscous, soft and slimy body between 1 and 9 cm in length, which in the case of the former is accompanied by a circular shell in which the mollusc lives. They move slowly and leave behind a trail of clearly recognizable transparent and luminous mucus. This plague usually occurs in outdoor crops and can be very dangerous for your marijuana plants, as these little guests have a voracious hunger, capable of causing serious damage to your crops.

Symptoms

  • Bites on the leaves, sometimes in the shape of a spider web.
  • Appearance of a trail of greyish mucus.

Treatment

  • Build a barrier: add a layer of lime, diatomaceous earth or salt sea sand to the edges of your cultivation.
  • Put some baits: make a small hole in the ground and place a container with beer and jam. It will attract you fatally.
  • It uses the predatory slime Ruminia taken off as a biological control measure.
  • Eliminate them manually: do it at night when they come out of their hiding places to feed. Help yourself with a torch. ——

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