Answer: Plain water is about the best defense against pests on herbs. The leaves of your herbs are quite tender so standard insecticides will burn them, to say nothing about the residues they might leave on the plants. Since you plan to eat the herbs, the best pest control is simply hosing the insects off with a strong stream of water. I can't tell from your description what the pests might be but if they are large enough to see, you should be able to pick them off by hand. Best wishes with your herbs.
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