I have a climbing pelargonium in the conservatory. Small eaten marks are showing on the leaves (not right through leaf though) At first I thought it was a leaf miner or similar, but the eaten bits are not really joined together. Found an odd aphid under the leaves (not many though). I've included a couple of photos. Any ideas and cures. Thanks.
Certified GKH Gardening Expert
This could, certainly, be aphid damage. This is typical of aphid damage. I use neem oil for the control of these. You will want to make sure that you don't apply this in direct sunlight, as it could burn the plants. Here is a collection of articles that will help you find many ways of controlling this problem: https://www.gardeningknowhow.com/special/organic/