I think it depends upon what pests you're trying to get rid of?
Also, I think there's a lot to be said for leaving them be unless they become a big problem as that will bring predatorss into the garden. If you use (for example) neem routinely you'll become dependent upon it.
So as an example, if you get greenfly in small numbers just watch for a bit and see if natural predators move in to feed on them. If not, try washing them off with water jet. Or better still, if your plants don't get stressed (over watering, under watering, too hot, too cold) they're less likely to experience an attack.
But there's a few ideas to try in this article - garlic, chili, soap, oil etc.
These natural, DIY formulas are safe yet effective for helping rid your garden of pests.
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