The red spider it is such a small parasite that it requires a careful look or rather a magnifying glass to be identified. It is a plant mite with the scientific name ofTetranychus urticae which often infests vegetable and fruit trees.
We can find it on tomatoes, beans, aubergines and many other vegetables, its proliferation is harmful to the plant that inexorably loses vigor.
Fortunately there are different methods to defend against the red spider allowed in organic farming, even using vegetable preparations that can be easily self-produced. The organic fight against this mite is all the more effective the sooner the threat is recognized and action is taken to counter it, let's discover the main remedies to the red spiders to learn defense strategies.
Recognize the attacks of the red spider
The spider goes to situate itself on the underside of the leaf, since the mite is tiny it is not easy to see the small red dots. The webs it forms are also very thin. Only when the infestation is really substantial can we see the clearly red leaf or guess the presence of cobwebs of this mite.
The presence of the parasite can be assumed when the plant presents a slow growth, leaves deform and lose luster until it becomes discolored.
What plants does it affect
What makes this red insect particularly harmful is its own ability to feed on different plants: in the garden, the spider mite can affect legumes (especially beans and green beans), solanaceae (peppers, aubergines, tomatoes) and cucurbits (pumpkin, courgette, cucumber, watermelon, melon).
Even in the orchard there are many trees that can suffer the presence of this harmful mite.
The insect with its tiny bites compromises the health of the leaves of the plant and with the web of cobwebs tends to asphyxiate the leaf. A plant can also die as a result of the parasite's action, while if the fruits are hit, the crop is ruined.
Red spider mite prevention
In organic farming there are many ways to defend the vegetable garden and orchard from the red spider, let's see the most effective ones.
Rather than having to kill the mite, the best thing is to create an unfavorable environment for its presence, thus preventing it from attacking the vegetable garden or orchard. Prevention is in fact always the most ecological and economical method to guard against adversity in cultivation.
This occurs primarily through biodiversity, which brings some natural predators of this small parasitic mite into the ecosystem. A formidable ally against the red spider is the ladybug, which devours them quickly, so it is important to know how to attract ladybugs to our cultivation.
Rain watering. Frequent rain waterings have the effect of driving away the spider mite from the plants. But be careful that it can be a double-edged sword because often wetting the leaves is an operation that can favor the development of fungal diseases.
Natural and macerated remedies
There are some plant essences that are unwelcome to the red mite and can be used to keep it away from our crops. This system is excellent because it is totally natural and also without cost, since the herbal preparations to be used can be self-produced.
The two best vegetable macerates that can be used against red spider mites are garlic and nettle.
Garlic is mainly repellent, nettle plays a certain insecticidal function thanks to the formic acid.
Counteract the red spider manually
You certainly cannot think of fighting the mite by catching it: it is too small to see and catch, however it is possible and often useful to counteract the threat manually. Check the plants e remove infested leaves it is a good way to contain the presence of spider mites.
If you can intervene when the infestation is in its infancy, the manual method can be effective. Obviously it is not applicable on a large scale but in a small vegetable garden before spending money on pesticides it is better to do what you can by hand.
Organic insecticides against red mites
The options allowed in organic farming to combat spider mites are varied, the most widely used organic insecticide is sulfur, but soft soap or white oil treatments are also useful for this purpose.
Sulfur-based treatments sprayed on the leaves can be helpful in fighting spider mites.
Sulfur is allowed in organic farming but is not free from contraindications: there are also remedies with a lower environmental impact (from soap to nettle macerate).
To carry out treatments with sulfur, you must pay attention to the temperatures, there is a risk of phytotoxicity which damages the plants.
Soft soap and white oil
The mite is very small and can also be killed for asphyxiation, by spraying an oily and tackifying substance that covers the entire body, suffocating it. For this purpose we can use two products, both allowed by the organic method:
- White oil
- Marseille soap (or similarly soft soap of potassium)
We have already talked about the ladybugs, as excellent predators of Tetranychus urticae , there are others too antagonistic insects which can help fight spider mites without resorting to pesticides.
Introducing insects is a biological defense method which, due to its cost and difficulty in finding it, is certainly not suitable for small-scale crops, while it is an excellent idea for professional organic farms. In particular it is a useful remedy in greenhouse crops, since the partially closed environment prevents the antagonists from dispersing elsewhere.
A biological defense can be implemented by releasing specimens of phitoseilus persimilis, a natural phytoseid predator of the spider.