Michael Douglas has compared marriage to an orchid, saying it must be nurtured to grow over time.
The 69-year-old actor - who separated from 44-year-old Catherine Zeta-Jones, with whom he has two children, for several months in 2013 - gave an interview to People to promote his new romantic comedy And So It Goes with Diane Keaton.
Michael said it was important not to let children or work get in the way of a marriage.
He said: "A lot of it has to do with age. When you've accomplished a certain amount in your career, you're not so focused on your ambitions. It makes you appreciate - and hopefully you do that sooner rather than later - the value of your partner.
"Like a lovely orchid, or anything else that's nurtured, marriage prospers and grows, but if it's ignored, it withers."
The actor is also quoted as saying: 'Marriage requires constant nurturing. Don't put it all in the kids. You cannot take marriage for granted at all.
"You can exhaust yourself with the energy you put into your children so there's none left for the two of you.
"It's a dangerous seduction to fall into, with the best intentions. You have to watch that one."
Michael has a son Cameron from a previous relationship, and two children Dylan, 13, and Carys, 11, with Catherine.
The actor also spoke about being open with his children about any problems in his relationship.
He said: "I'm more and more prone to tell kids just about everything. There's been a whole school of thought about things you should not tell children - if there's a problem in a relationship, [people say], 'Let's not let the kids know.' Kids know. They know everything. I would err on the side of pretty much sharing everything. They can digest it, you know? It's life."