Would a white dress with black floral print be inappropriate for a wedding?

A little background on the wedding: My brother is getting married in September. I am not part of the wedding party, but I am likely to be in some pictures. The wedding starts at 4pm and is outside, while the reception following is inside. I have no idea if I will be sitting near the wedding party during the... show more A little background on the wedding:
My brother is getting married in September. I am not part of the wedding party, but I am likely to be in some pictures. The wedding starts at 4pm and is outside, while the reception following is inside. I have no idea if I will be sitting near the wedding party during the reception. There isn't really any dress code that I know of, and the couple isn't really that formal, nor are the families.
Description of my outfit:
I went shopping and after 5 different stores, I finally found a dress I liked that was affordable and comfortable. The only problem is that after I got home and was thinking about it, I started to worry about the color choice. The dress has a white background with medium size black roses all over it and black edging. I also plan to wear a short black cardigan over the dress with chunky black jewelry and black flats.
The issue:
I know that there are rules about wearing white to the wedding and about wearing black. I tried to get some opinions online, but it was mostly 50/50. For the most part, it seems that the black would be okay, especially since the wedding is late afternoon/early evening. I am still not sure about the white though. At the time, I thought it wouldn't be an issue due to all of the black accessories and the black print on the dress, but after reading all the comments online I am not so sure. I asked my brother and the bride for their opinion, but I haven't gotten an answer yet. Even if the bride does okay the dress, I don't want to have to worry about the rest of the guests talking about my dress choice being inappropriate.

Here are the links to the items I will be wearing:

Dress
http://www.dillards.com/product/Jessica-Simpson-Woman-FloralPrint-Dress_301_-1_301_502987297?df=03707777_zi

Cardigan
http://www.dillards.com/product/London-Times-Cardigan_301_-1_301_502946032?df=03687114_zi_black

Shoes
http://www.payless.com/store/product/detail.jsp?catId=cat10376&subCatId=&skuId=092497055&productId=69922&lotId=092497&category=&catdisplayName=Brands

Possible Jewelry
http://www.jcpenney.com/dotcom/jewelry-watches/mixit-fashion-necklace-hematite-flower/prod.jump?ppId=1e7d7f0&navState=navState-:catId-:subcatId-:subcatZone-false:N-:Ns-:Nao-0:ps-24:pn-1:Ntt-hematite:Nf-:action-search&catId=SearchResults

Thanks for your help!!!
3 answers 3