Only two plants have them in different areas of garden. This is unsightly. Could it be slugs? I use Sluggo if needed.
I have the brown streaks on several plants here. I don't know if the weather there has been like where I live, up & down temps, but that is what I attribute it to. We had a hard frost after weeks of 80 deg temps. A couple of plants looked like they were dying. I followed advice from people here to cut them back. I did, they are both growing back nicely & one has scapes. Others I just cut off the streaked leaves til I got tired.
Probably leaf streak. Look further down to an entry on rust, and Floota gives the name of a product that would clear it up.
Here are photos of leaf streak. Clearys 3336 is one of the products mentioned to help clear it up.
Here is a link that might be useful: Leaf Strak