Give them the right soil conditions
The dwarf azalea under the elderberry tree has clearly been struggling with shade and drought, and along with my other azalea in the border nearby, it looks like it might have issues with pH as well. It’s always worth experimenting with less-than-ideal conditions as plants will often grow regardless – if a bit more slowly. But, when ericaceous plants like these start to show interveinal chlorosis, where the veins remain green and the tissue in between goes yellow, this indicates there’s too much lime in the soil. So, I’ve rescued them and potted them into containers of peat-free ericaceous compost, where they’ll soon perk up and thrive.