A natural insecticide will kill insects, that much is certain. Natural insecticide has been used for centuries, at least. If you are a curious person, you might like to know how natural insecticide kills insects.
Diatomaceous Earth is a natural insecticide made of the skeletal remains of plankton. What it does is to puncture the bodies of the insects. Then, it dehydrates them. When this natural insecticide has done its work, unwanted insects will dry up and practically blow away.
Rotenone is a natural insecticide, as well. It is made from the roots of the derris plant. It does its killing by poisoning the stomachs of insects. However, it is slow-acting and needs to be reapplied often for maximum effect.
Rotenone also seems to keep insects away from plants. It will keep the insects from growing and will stop them from eating if they are not adequately poisoned. Sabadillia also kills by stomach poison.
From Ecuador and Kenya comes a species of chrysanthemum that yields a natural insecticide called pyrethrum. This natural insecticide destroys insects by paralyzing them. It works instantly and it works on most types of insects.
The only problem is that the pyrethrum will often wear off. The insects will come around after awhile. They are not killed after all. For this reason, it is often combined with a poison that finishes the insects off.
Natural insecticides used in the termite control industry work in a different way. They cause the termite to lose their appetite. In fact, they can’t eat at all.
The natural insecticide will cause the termite to be disoriented due to damage to its nerve endings. (People and animals do not have these same nerve endings and so are safe.) Due to all these problems, the termite will eventually die.
A bacterium, Bacillus thurengiensis or Bt, is another natural insecticide that is popular these days. It is best used when the eggs of insects are just hatching. The young come out, eat the toxin, and are poisoned. They will stop eating and die of starvation.
Neem preparations get rid of insects in many ways. This natural insecticide repels the offending bugs by means of an active ingredient that mimics an insect hormone. It makes it hard, if not impossible, to digest food. It stops their cycle of reproduction. It works well on insects that chiefly eat leaves.
Some non-plant natural insecticides do their work by dehydration, as Diatomaceous Earth does. Chalk dries out insects on contact. Mineral oil either dries out or suffocates its victims.
A mixture of cow’s milk, flour and water can be used as a natural insecticide. It is very good at killing the eggs of the insects. It also destroys insects themselves, by suffocation.
Corn meal can be sprinkled around plants to kill insects. If a tomato hornworm happens to eat some, the cornmeal will swell up in the insect’s stomach. The insect will explode.
There are all kinds of ways to kill insects. Some are by simple poisons. Some ways are more exotic ways. It may not really be important to know how a natural insecticide kills insects; only that it does.