What does a grandmother wear to her grandson's wedding? Should

Musicmaker :
I would ask the bride or groom. When my niece got married her grandma asked what color she should wear and my niece said she could pick whatever color she wanted.

Musicmaker :
I think it is OK for the grandmother to wear whatever she wants. In my opinion, it would be nice to coordinate with the bridal party rather than actually matching them exactly.

Musicmaker: Check with the bride. That is usually the best way to get your answer. Your going to be beautiful in whatever you wear. Just having you there is a blessing.❤️

Musicmaker : Good advise given here.
Enjoy your grandson & his bride's wedding!

I would say any color except black or white. Yes, ask the bride if there is a certain color she would like, and what length and style.