Before they woo or wow sweethearts, hundreds of millions of cut flowers get a critical look over from U.S. specialists looking for pests and disease.

With Valentine's Day approaching, it's a busy time of year for the 2,300 U.S. Customs and Border Protection specialists nationwide who pore over flowers coming into the United States, The Miami Herald reports.

The specialists inspect the flowers in chilled warehouses like the 23 within a 5-mile radius of Miami International Airport.

Specialists in one warehouse stand behind long tables with cartons of palms, chrysanthemum and long-stem roses in shades of red and peach and white.

The specialists grab bunches by their stems, turn them upside down and pat them, shaking loose dirt and the occasional bug.

"I am looking for anything that can come in and cause harm," said U.S. Customs and Border Protection agriculture specialist William Oldrup, examining debris from a bunch of palm fronds from Guatemala.

The specialists are on the lookout to guard against harmful insects and diseases entering the United States from grower countries, including Colombia, Ecuador, Mexico and the Netherlands. The inspectors eye the flowers and plants for pests and traces of diseases -- including thrips, aphids and fungi.

Last year, customs agents processed about 802.5 million cut-flower stems during the six-week Valentine's Day season, Jan. 1-Feb. 14, and the number is expected to be about the same this year. The inspections last year prevented 3,400 plant pests from entering the country on cut flower imports, the customs agency says.

And maybe saved many a sweetheart an unpleasant surprise.