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.
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.
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.
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.
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.
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.
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.
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.
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.
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.