Fall or autumn has always been referred with crisp, chill and I am thinking blue or dark nail polish shade is fun color for this season. I love blue color and there are various blue nail polish shades like navy blue, dark blue, bright blue etc. that you can find at the store. Certainly I'm not sure which kind of blue shade work with my skin tone. Not too vivid and not too pale for sure. I tried this blue shade called "blue lagoon".

 
This shade is almost same color with this plant. I applied it on my fingers and toes. It is kind of light and metallic blue color.

Some say it was a major trend for spring but I think the color is suits for fall. Check out some celebrities who are fans of blue nail polish.

pic from squidoo
Personally I feel blue is edgy, great hue, and this vibrant color sometimes intensify my mood. 

I might try other kind of blue.