Hey @archeothot, thank you for all of your great suggestions to help get rid of aphids. I will look for rapeseed oil. Would I dilute black soap into water like I have done with washing up liquid? I can only hope some of these remedies will get rid of them.

I looked up perennial maritime Crambe, some of the photos I saw do look similar to the plants I have. I will keep watching and see how the plant develops!