Nick Lachey tries to be ''spontaneous'' to keep his marriage on track.

The 40-year-old singer, who has 17-month-old son Camden with his wife of almost three years Vanessa Lachey, likes to surprise the brunette beauty with romantic dates and gifts once their little boy is asleep.

The 98 Degrees star told ABC News: ''You have to keep it spontaneous - surprise dinners, flowers, concerts. They all make a difference.''

He added: ''Our time together is after we put Camden down for the night. So much of the rest of our day is dedicated to him and work, but we always make sure to share a glass of wine and some time together at the end of our day.''

The couple are planning to enjoy a romantic trip together for Valentine's Day on Friday (14.02.14).

The 'What's Left of Me' singer said: ''We are going to celebrate this year by taking a little romantic getaway together. Always nice to spend a weekend away from the hustle and bustle and enjoy each other.''

The star, who was previously married to Jessica Simpson, admitted last year that he and Vanessa hope to have at least one more child.

He said: ''I think we've talked about two more but if the next one is a girl it may be tempting to just have one of each. In a perfect world we'd have a couple of boys and then finish off with a daughter. If I can orchestrate that I'd be good.''