What should go with this dress?

[fluffyanimal]

Please help, style and beauty gurus - I'm clueless!

I'm going to a wedding in a couple of weeks. It's quite informal, the daytime part is open air, involving picnics, and the evening is in a church hall. So (also bearing in mind I'll be running around after my small DC), I have got this dress which I thought was smartish but not too formal, comfy, plus I'd be likely to wear it again. (Link, if you want to see it close up: www.fatface.com/Maxi-Dresses/Bea-Indian-Garden-Maxi-Dress/invt/77901 )

If it's not that warm, I'll want something to go over the top. I already have a cream velvet blazer (quite short), but I tried it with the dress and I wasn't sure, plus DH said it spoiled the look of the dress. Please help me find an alternative. It could be a jacket or it could be a cardigan, but I don't know what style or what colour to choose.

I'm size 14 and I can't afford to spend more than £50. Over to you clever ladies!

Any ideas?

I love that dress. How about an angora style cropped cardi, in a muted colour monsoon often sell them?

uk.monsoon.co.uk/uk/women/shrugs
I'd wear it boho style, with a few flowers pinned into hair at the back.

uk.accessorize.com/uk/accessories/hair-accessories
Accesorize have so many flower clips/bands in at the moment. This is just what I'd do, you may be looking at these links in horror!

Not at all, thank you! I was wondering about some kind of floral hair accessory too. So you think a short cardi, right? Do you think a kind of neutral/stone colour would be OK (that colour is in the flowers on the dress)?
I just found this, would this be wrong? Too casual?
www.woolovers.com/cotton-silk/womens/tie-front-cardigan.aspx

(I'm so unadventurous with clothes and always buy the same things...)

What about something like this?

Thanks chocolateyy, I think chiffon just wouldn't be warm enough if it was a day like today. OK, please help me choose:
This:
www.marksandspencer.com/open-front-tape-knit-cardigan/p/p60069024?mfPartNumber=T386207B&carousel=FUNV_RR#
This:
www.woolovers.com/cotton-silk/womens/tie-front-cardigan.aspx in either linen or navy
This:
www.woolovers.com/cotton-silk/womens/ladies-v-neck-cardigan.aspx in either linen or navy
Or a big pashmina:
www.thewoolcompany.co.uk/diamond-weave-fine-wool-silk-shawls.html
???

I wore something similar to Glyndebourne last summer. Wasn't all that warm in the evening so I covered up with a cropped cashmere cardi from Brora and it worked very well. As it fell just above the waist it emphasised curves in a good way. They are expensive, but there are always a few on Ebay. Warning- size up, they come out small.