I was at the same wedding as Knitting Gene. It was such a charming venue, but definitely cold, plus there were some treks along muddy pathways.
I wore wide leg charcoal grey velvet pants and (a favorite current piece of mine) an Anthropologie silver camisole. I topped this with a cropped, lightweight, short sleeved sparkly taupe cardigan, which honestly made the outfit feel more mother-of-the-bride-y than I would have liked, but it was necessary for extra warmth. I took it off for dancing.
For the outdoors parts of the evening, I wore my cream colored asymmetrical drape-y wool coat from Garnet Hill, and my workhorse blush scarf with a pompom fringe. I have dressier coats that might have worked better with my dressy outfit, but this one felt perfect for the rustic setting, plus it was warm, and I was happy.
Normally I’d wear velvet flats with these pants but because of the outdoorsy venue, the mud, and the possibility of rain, I decided to forego those and instead I pulled out a pair of basic black booties that I’ve held onto for decades because they are, just occasionally, very useful. This was just one of those occasions.
If you’re going to be outdoors and don’t have footwear like that on hand, you could look for a pair of used shoes or boots that you don’t have to worry about wrecking. This suggestion comes by way of my goddaughter/Knitting Gene’s daughter, and I thought it was brilliant. She suggested Buffalo Exchange and there’s also always Goodwill. I definitely would have done that if I hadn’t had my trusty old booties.
I look forward to seeing what you pull together. Have fun!