From the article;

The idea of offering celery as a Valentine's Day gift to your loved one instead of chocolate might send the wrong message, but scientists working to improve the rose genome could make the low-calorie stem a popular Feb. 14 present after all.

It turns out that one particular gene from celery — mannitol dehydrogenase — greatly improves the life and quality of rose petals when that gene is spliced into the rose genome. So in an effort to help you get more value from your Valentine's Day gifts, North Carolina State horticultural scientists Dr. John Dole and Dr. John Williamson are leading an effort to insert that gene into roses to create a new superflower less prone to wilt and more resistant to disease, according to PhysOrg.com.