Hello, I have a milkweed plant that seems to thrive but it leaves look bad and I can not find any images or information online that tells me if what I'm seeing is normal or something I need to treat. The leaves get a reddish cast to them that gradually overtakes most of the leaf as it turns yellow. It happens on the adult plant and on the babies growing under it. It's the older leaves that it happens to, so I wasn't sure if this is just how they age (I suspect not though!). The red is best described as brick red or the actual color of rust on iron - but the pictures I have seen of leaf rust look nothing like it. There are no pustules under the leaves - just a reddish cast to the leaf that spreads. Does this sound familiar to anyone? I'd like to treat it if possible if it's a problem, but am unsure how since I do get monarchs!
Thanks!