Waiting to know because mine look like this as well this year, and for the last few year. My rosemary used to be gorgeous. Last few Summers have been quit wet and HUMID and there are insects around never seen before.

You don't say where you're located, so, I'll take a guess at: the roots dried out in the recent past and now you're seeing it.

I live in East Tennessee and these plants get watered once a week.

Besides cutting the watering, anything else I can do to revive them?

Q. Are these established palnts or new to you?

They were planted 2 years ago.

Now I'm wondering if they got sprayed with something that is killing them... perhaps drift from a neighbor.

I don't believe so. I'm in a rural location with neighbors a good distance away. I've checked for insects and don't see any.

The stippling does imply a sap sucking pest.

My rosemary looks much the same though not as bad as yours. We have been inundated with rain and it occured after the rain started. i just moved mine, its potted. They do prefer to be on the dryer side. Im in N. FL. I never see pests on it. just sharing.

Aside from our recently much more HUMID summers in NJ (without any real drying air masses), I have noticed flying insects around the plants when I brush the leaves, I am sure they are involved in the discoloration. Though the lavenders seem not as well damaged by either the weather or the bugs. Not sure what's been going on with the rosemary though.

Not sure if it's insect related. I have tried several times to disturb the plant and look for anything flying away and I haven't seen anything.