Pyrethrum: the natural insecticide against mosquitoes

Pyrethrum is a natural insecticide useful for repelling mosquitoes from gardens, vegetable gardens and orchards and active against various plant parasites.

Although it is a natural substance, pyrethrum must be used with care to avoid harming beneficial pollinating insects. For this reason, it is useful to resort to automated systems capable of distributing the correct amount of pyrethrum in outdoor areas.


  • What is pyrethrum and what is it for
  • Precautions for using the pyrethrum
  • How to choose which pyrethrum to buy
  • The new iZanz ecological system to keep mosquitoes away

What is pyrethrum and what is it for

The Pyrethrum is a natural insecticide pyrethrin, a natural substance that is extracted from the flowers of Chrysanthemum cinerariifolium.

Pyrethrum has always been used, since ancient times, to ward off plant parasites and annoying insects such as mosquitoes. Once upon a time, pyrethrum flowers were dried and ground up to obtain a powder to be dispersed in water: the solution was then sprayed on the plants.

Today, pyrethrum-based products are sold in the form of spray liquids to be distributed on plants in the vegetable garden, in orchards or in the garden.

The insecticidal action of pyrethrum eliminates mosquitoes very quickly. In addition, any pyrethrum residues on the plants discourage visits from parasites.

The pyrethrum acts by contact with insects, blocking their nervous system, is not absorbed by plant tissues and the molecule rapidly degrades in the environment, because sunlight breaks it down.

Pyrethrum is considered effective and safe, is characterized by low toxicity and its use is also allowed in organic farming. However, it must be used according to the rules and common sense like all things.

Quickly kills mosquitoes . Pyrethrum extract works by blocking the nervous system.

  • It acts by contact, but it is not phytotoxic, it does not damage plants, because it is not translaminar (i.e. it is not able to penetrate plant tissues). The consequence is that if the parasites are hidden among the leaves, for example among the thousand folds of a head of cabbage, they can escape the treatment. Generally at least two treatments are performed for this very reason.
  • It is not a systemic treatment, i.e. it does not enter the plant fluids. It degrades quickly in sunlight and is washed away if it rains.

It can be very useful in the vegetable garden and in the orchard due to its effective killing action on many plant parasites, as well as in the garden to defend against mosquitoes. However, care must be taken in using it . The fact that it is natural does not mean that it can be used without any precaution

Pyrethrum extract is therefore a natural substance. But having the characteristic of degrading to solar light and heat, pyrethrum-based insecticides are today produced with a chemical support that extends their duration and effectiveness from four or five hours to eight / ten in order to reduce the amount of use. Pyrethrum insecticides are however to be preferred over other pesticides, because the starting point remains of natural origin and for their biodegradability. There are also insecticides made with synthetic pyrethroids with a molecule similar to the natural one, but more resistant to sunlight and therefore with a more prolonged effectiveness.

Everything you need to know about the insecticidal action of pyrethrum can be summarized in points:

Precautions for using the pyrethrum

Pyrethrum is a not very persistent substance , a characteristic that can reduce its insecticidal action but which is also a great advantage if used in the vegetable garden or in the garden, since it degrades rapidly.

When treating vegetables this is particularly important: the treatment has a short waiting period and therefore the insecticide can be used even shortly before harvest. In the garden, on the other hand, the advantage of its rapid decay is that it does not leave toxic residues that could annoy pets, children and even adults who live in the green space, which is why it is often used as an anti mosquito insecticide.

Pyrethrum degrades in particular when exposed to heat and sun. Under these conditions its effect wears off. These characteristics combined with the low toxicity towards warm-blooded animals make it a non-harmful and natural treatment, which we can use organically in the garden. After two or three days it will be possible to eat the treated vegetables.

However, you must be very careful: it is recommended to read all the warnings on the package and to strictly comply with them . Each insecticide has contraindications and must be used with common sense.

How to choose which pyrethrum to buy

On the market there are numerous pyrethrum or pyrethroid-based insecticides, it is very important to know how to choose the best and environmentally friendly products.

Important indicators are then the class of toxicity and the time of lack , ie the duration of the activity in the environment (choose the one with the lowest possible value).

In general , pyrethrum is found in liquid form , easier to use safely than any pyrethrum powder. We find liquids to dilute and nebulize, or even pyrethrum spray, suitable for those who grow few plants and choose comfort.

The new iZanz ecological system to keep mosquitoes away

Today there are ecological disinfestation methods that spray pyrethrum or pyrethroid-based insecticides automatically, reducing their use to a minimum and maintaining their effectiveness.

This is the case, for example, of the innovative system designed by the Italian company iZanz , for the control of mosquitoes outdoors.

The system involves the installation of spray nozzles at a distance of four meters from each other along the perimeter of the area to be protected from mosquitoes.

Once installed, iZanz remains invisible, therefore it does not impact the aesthetics of the garden and automatically produces a fine and imperceptible mist of water and low percentage natural pyrethrum.

The iZanz system is programmed to spray the 1% insecticide in the water for 70 seconds twice a day, at sunrise and sunset, so as to eliminate only mosquitoes and not harm other beneficial insects such as bees and butterflies.

Thanks to this system it is in fact possible to keep mosquitoes away without having to use and breathe insecticides that are harmful to the environment or apply repellents that are potentially harmful to the skin.


Leave a Comment