Guest dress code request

Hey guys,

I have a slight dilemma regarding rules for guest attire and if it's okay to request it.

If you think it's okay to have a dress code so to speak, how do you communicate it and where?

Since the time I was young I have always thought that people who wear black to a wedding, especially women, are disrespectful. To me (I guess I went to too many funerals when I was young) I associate it with mourning and sadness. (I get that most men's suites are black so it's not as bad?)

Its weird, I know. I mostly wear black everywhere else and I think it's fine. However for weddings I feel like it should be a celebratory and colorful occasion. Plus my wedding is outside in the spring so I'm clearly going for lots of color and brightness. (And black gets hot in the sun!)

I know it's been the trend that everyone has that little black dress they want to re use for multiple occasions as well.

Would it be acceptable or appropriate to request that our guests refrain from wearing black? Its a small and casual wedding and reception so formal attire definitely isn't expected. Giving guests hopefully more of a broad selection of attire.