Wedding Colours

Me too! I was briefly considering having a deep blue as one of our colours, and you can be sure there would have been peach/coral involved!

Ooooh, beautiful colour combo!! Would be awesome if it's a colour you're going to mix into the flowers!!!

I think the other girls are right, a more soft, maybe even pastel colour, of yellow, pink or blush, would really compliment blues/greys. Honestly, I think red isn't a really "bright" colour in the way you want it, it's just bold, and may come off dark for a summer wedding. Something truly "brighter" (lighter) would be a great way to balance any darker colours.

Softer Palette

But, if you were drawn to red due to it's boldness, maybe some more tropical colours for a July wedding? I had a cousin who used teal, orange and fuschia, and it looked beautiful. Incorporating orange and/or teal would definitely be a unique, bold look with navy. And very summer-y.

Bold Palette

I think yellow or pink flowers would look great with your blues and grays! You could still use a lot of white flowers and greenery and just add few colorful touches!

Pinterest is great for searching wedding color palettes, here's an example centerpiece I found that would look awesome with blues and grays:

:: Pinterest

My first thought was a blush/pink.. but yellow would be nice too!

You also don't need to do a pop of colour, I'm not really. For example:

My dress is ivory, brides maid dresses are a silvery-grey, groomsmen are in a dark grey and my groom is in a light grey suit.

The guys will wear pale yellow ties and pocket squares and the bridesmaids will have white/pale yellow bouquets.

I'm super pumped for the soft and muted pallet.

Bright pinks or yellows would look fabulous with the blues

Gold would look marvellous with these colours!!! And adding greenery. I'm not sure about the red, although it is an accent colour, it may end up looking fabulous.