If you have pests at home, you want them gone quickly. In the shops you will find roughly two kinds of products: sprays and baits containing an insecticide, and traps that lure and catch insects. Which one suits your problem best? That depends on the insect, the size of the infestation and where it is.
What does an insecticide do against pests?
An insecticide is an active substance that kills insects. A spray works on contact, a bait works through food that the insects carry back to their nest. That is useful for an acute infestation of crawling insects such as ants or cockroaches. Two caveats: a spray only reaches the insects you can see, and the breeding site stays. With repeated use of the same substance, insects can also become less sensitive to it.
What does a trap do against pests?
A trap lures insects with a smell, a colour or a pheromone and holds on to them. A fruit fly trap uses the smell of fermentation, yellow sticky traps attract fungus gnats with their colour, and a moth trap lures males with the pheromone of their own species. A trap therefore targets one kind of insect. It also catches the first individuals, so you notice an infestation early.
How well a trap works can be measured. The Super Ninja fruit fly trap works without insecticide: the lure consists of 37.5% vinegar and 5% apple juice concentrate. In independent testing under the European Biocidal Products Regulation, the trap caught 84.9% of fruit flies within 24 hours, with competing food in the same room (SAGEA, report 4540.SAG, 2021).
Why is hygiene the first step against pests?
No spray and no trap will solve an infestation while the source remains. Fruit flies breed in overripe fruit and dirty drains, fungus gnats in wet potting soil and pantry moths in open packaging. Remove the source, store food in closed containers and keep drains clean. That is the step that makes the difference.
Insecticide or trap: which should you choose?
Flying insects such as fruit flies, fungus gnats and moths are best caught with a trap designed for that species. With a large infestation of crawling insects, an insecticide may be needed to reduce the population quickly. In every case: tackle the source first and use a trap to check that the problem stays away.
Use biocides safely. Always read the label and product information before use.