@lize You would be AMAZED what a viewer will accept as long as you present it confidently. You mentioned that this image is about:
lot of little DIY things people can do for biodiversity in their garden
In your position I would make the judgement call this this is more important than the illusion of space (which is effectively what painting atmospheric perspective is)
I would feel confident setting aside the rule of atmospheric perspective because you can create the illusion of realistic space using other tools: linear perspective, object overlap, varying degrees of detail, color and hue etc.
Again, use what makes sense and disregard the rest.