If you're ever having trouble coming up with a colour combination, try going to a piece of your favourite DSP. In this case, I went to the US Holiday Mini for my colour combination! I would never have thought of putting Real Red, Baja Breeze, Garden Green and Blushing Bride together, but I love the result.
And here's a TIP: to secure a knot of ribbon in place, attach your ribbon to the card first with a brad, and then simply tie your knot (a single one will do) over the top of the brad. Voila - a perfect knot that will never fall off! You can tie bows in place in a similar way. No adhesive required (and you can use up brads in ugly colours too ;o)