I also have the same black flecks on my tricolor sage plant that I bought a month ago. I live near Philadelphia, PA, and bought my sage plant at a nearby farm. They are tiny, hard specks (like dirt) that sit on the leaves and stems. I reviewed 'Southern Blight' and the nematode advice posted, but it is not either of those things. The 'specks' do not seem to be a bug, or even alive in any way; they are the consistency of dried coffee grounds, or black pepper from a pepper shaker, and can be easily brushed off. I brush the flecks off, and then a few days later those specks are all over the plant again, and on the kitchen counter where the plant sits. Just like Katie said, they are like black specks of dirt. At first I thought they might be seeds, but I honestly don't know anything about sage plants, and I'm sure you are probably all laughing hysterically by now. My plant seems to be otherwise healthy.
I also have the same black flecks on my tricolor sage plant that I bought a month ago. I live near Philadelphia, PA, and bought my sage plant at a nearby farm. They are tiny, hard specks (like dirt) that sit on the leaves and stems. I reviewed 'Southern Blight' and the nematode advice posted, but it is not either of those things. The 'specks' do not seem to be a bug, or even alive in any way; they are the consistency of dried coffee grounds, or black pepper from a pepper shaker, and can be easily brushed off. I brush the flecks off, and then a few days later those specks are all over the plant again, and on the kitchen counter where the plant sits. Just like Katie said, they are like black specks of dirt. At first I thought they might be seeds, but I honestly don't know anything about sage plants, and I'm sure you are probably all laughing hysterically by now. My plant seems to be otherwise healthy.