My mom is still alive, but today I went to the cemetery and put a rose on my father’s grave. It’s been eight months.
We are not a “visiting gravesites” type of family. Heck, most of our recently deceased don’t even have gravesites. It would not have occurred to me to do it.
I do understand why some people do it.
Here’s the paper of record on the subject.
I can see it being a thing, or not. For me, I visited my mother’s grave and put flowers on it once, when I happened to be in the area, and I didn’t feel any particular way about it. I had been there before a couple of times, as my father’s grave is in the same place. I do miss them, but it has nothing to do with putting flowers on their grave and that doesn’t help.