I know that this response is coming after the fact, but in the past I have given a beautiful card with a message indicating that their special gift is in progress and will be presented in..... (You fill in the blank with the amount of time your feel is appropriate).
I just gave a quilt last week-end that was slightly more that one year after the wedding. The quilt was finished earlier but The grooms mother suggested that I wait for the couple to travel home from out of state to present them with the gift at a family reunion. It worked.