Colorful blast of waterfront tulips is Valentine’s Day delight [...] the Palo Alto couple drove to San Francisco Saturday for the annual Tulipmania festival at Pier 39. Holding hands, they walked among the vibrant display of 39,000 colorful tulips, interspersed with clusters of poppies, primrose and parsley. “This experience makes me feel very warm inside,” she said, smiling. Flower containers were perched around every corner at the pier — filled with bunches of lavender, yellow, red and orange tulips. Most of the blossoms were opened to the sun Saturday, but late-blooming bulbs were also planted, meaning there are more to come this season. Michael Kyelberg, a Tulipmania tour guide and landscaper at the site, talked of the merits of each flower bed and encouraged people in the tour to get down on their knees for a better view. “The colors are like a piece of artwork,” he said, gesturing toward a mixed red and yellow tulip. A girl in a purple sweater interrupted — “I thought tulips could only be one solid color,” she said. Free guided tours depart daily at 10 am from the Pier 39 entrance plaza, and self-guided tour manuals are also available online.