Which herbs are you growing? Different herbs have different requirements, but to be on the safe side and try to please everyone, keep your soil at neutral ie pH 7.0.

Herbs, as discussed before are just like calling something outside growing as a 'plant'... You need to specify the kind or types of herbs you want to plant. Also are they for pots or directly in a garden? Hundreds of thousands of herbs out there, and many are actaully weeds. For most herbs, they are not as fussy as some other 'plants' like blueberries for instance. Blues need soil pH at below 4.5. Many herbs do well at down to 6 up to 7.8. Avoid adding fertilizers unless there are low soil nutrients such as growing in gravel or sand.