Reddish spots on Rudbeckia plant from a pest of some sort?

Question: Reddish spots on Gaillardia plant from a pest of some sort?

 

Answer: No I don’t think its pest damage. Its not uncommon for some stems of rudbeckia to be spotted like that, the plant is definitely sad, but it has nothing to do with the red spots!

Question: Okay thanks! She did send some pictures of a few others and it didn’t look like they had spots like this. Is there a reason for this, so I can relay it to customer?

Answer: Its just a plant pigment cell called anthocyanins that are responsible for purple/ red coloration in plants. I’m not entirely sure why rudbeckia stems have it- but its definitely not a cause for concern. For a fun lil fact- anthocyanins are kind of considered sunscreen cells for a plant- often times when a leaf turns purpley red its a sign of light stress and the anthocyanins are providing photoprotection. again, not entirely sure of why some stems have this… and the function of these cells in stems appear to be heavily debated!

PubMed Central (PMC)PubMed Central (PMC)
Red-stemmed plants are extremely common, yet the functions of cauline anthocyanins are largely unknown. The possibility that photoabatement by anthocyanins in the periderm reduces the propensity for photoinhibition in cortical chlorenchyma was tested … (174 kB)