EDIT: Apparently nobody read what I said. I did not say can I tell adults what to wear. I said can I even say the decor and such will have fall colors so guests can know ahead of time. I know most people won't care, but I wondering if few would want to know. I never wanted to make anyone feel like they have to wear any color.
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Can I asks guests to prefer fall colors if they can (the wedding is in the fall), but not require it or make it mandatory or make anyone feel like they NEED to buy something totally new just for the wedding?
I'm not looking to control my guests, just give a suggestion to anyone who has many choices of clothes to wear, but not sure what to pick. Or if there's anyone who wants to buy something anyway, or to some guests who I know don't have any formal clothes anyway. If someone wants to wear spring yellow or baby blue to the wedding, I'm fine with it. Is it not polite to make a friendly suggestion? Or is it rude to even say the wedding will have fall decor?
Re: Can I tell guests the colors of the decor?
I promise that it doesn't matter whether or not your guests match your colors. I've NEVER been to a wedding where guests matched. Don't let themes or pretty pictures become more important than your family and friends.
Nope. you should never tell your guests how to dress unless there is a dress code dictated by the venue (like, men must were jackets or women must cover their shoulders), or it is a truly black tie event.
Websites/blogs where our wedding has been featured:
http://www.dapperq.com/2013/11/a-very-dapper-wedding/
http://www.onabicyclebuiltfortwo.com/2013/10/wedding-christina-g.html
http://4realequalityweddings.com/2014/05/16/g-christina/
Just let your guests wear whatever they want to your wedding. Honestly guests could give two shits about what your theme is. All they care about is seeing you and your FI get married and celebrating with you. No one and I mean no one cares that much about your color scheme or theme to coordinate their attire. So don't tell your guests if they prefer fall colors that they can most certainly wear them or anything else for that matter. You will not be any less married if your guests are coordinating with your decor.
They'll walk into your wedding, notice that it looks nice..and then go about enjoying the ceremony and reception.
Food, drink, atmosphere (are they comfortable, is there good service by any wait staff there, are there enough facilities, is there enough food, is it too hot or too cold, music...and with music what they will tend to remember is if it was BAD or annoying.). That is the stuff they are going to notice and remember.
Second - unless someone chooses to wear something REALLY out there (and I mean REALLY out there like a costume of some sort) no one is going to really pay any attention to what any of the other guests are wearing. They won't notice if they coordinate. And I guarantee they aren't going to notice if they coordinate with some "theme"
What the other ladies have said is correct - it would be rude to even "hint" as to what colors, etc people should wear. And...the fact is, there would be no reason to "hint" because no one is going to care or notice.
I'm not planning my wedding to be a fashion show.
You can theme your wedding all you want. And you can have that theme on all your paper products and wherever else you want. However, you cannot "preference" people toward that theme.
Your guests don't care what your theme is. And honestly, if I saw pictures of a wedding where all the guests coordinated, I would think "What a crazy rude bride who forced her guests to wear her colors."
Edit: stupid autocorrect
When is the last time you coordinated with the wedding colors as a guest?
I specifically asked this with the condition that I DO NOT WANT TO TRY TO FORCE PEOPLE. I know forcing people is rude, thanks.
As for why I put "theme" in quotations: I hate "themes" with wedding. The theme of your day is a wedding. You are getting married. You don't need any more "theme" than that. Too much "theme" and weddings become tacky and cliche. Lots of brides think they need "themes" and I really and truly believe that the entire concept of "themes" came into existence simply so that the wedding industry could generate more money from selling crap to people planning weddings.
As for your invitations: they are really the only way to hint at the formality, etc. of your wedding. Here is where people are going to get a really good idea of how formal your event is.
More formal invitation which lists a more formal venue = guests will dress more formally for your wedding.
Less formal invitation that lists a less formal venue = guests will dress less formally for your wedding.
Evening wedding/reception = guests will likely dress more formally
Afternoon wedding/reception = guests will likely dress more casually
If you are having a ceremony and reception at a barn in the afternoon...you can expect more casual attire.
If you are having a ceremony at a church and then a reception immediately thereafter at a ballroom...you can expect more formal attire.
For ages, people have used this kind of common sense in how to dress to attend events and weddings. I promise you, you do not need to tell them.
If folks can't figure out from your invitation what is appropriate, then they will use word of mouth to figure it out. You do not need to write anything on the invitation and it is rude to do so.