Just wondered if you know what’s happening with my geraniums?
From your description and photograph, it would appear that your geraniums are being attacked by either slugs or snails.
To confirm this, we suggest heading out to the garden with a torch to observe your plant at night when most plant damage occurs.
While the pungent odour of geraniums is often a defence against chewing insects and/or slugs and snails, in particularly hot/dry summers, almost all leafy growth is very appetising to these pests!
To treat the problem, scatter slug pellets around the base of the plant (there are pet and child friendly products available). Remember that as temperatures cool, this problem will slowly diminish.