TUCSON, Ariz -

Authorities who monitor vehicle traffic at the Mexico border are issuing a Valentine's Day warning.
   
They say travelers wanting to bring flowers into the United States from Mexico are barred from bringing in certain plants that are used in floral arrangements.
   
U.S. Customs and Border Protection says there's a longstanding ban on bringing in chrysanthemums, gladiolas and orange jasmine from Mexico into the United States through passenger ports of entry.
   
The ban is intended to prevent harmful pests and fungi from entering the country.
   
Roses, carnations and other flowers can be brought into the United States once after border-crossers clear inspection.
   
Still, plants potted in soil are prohibited from being brought into the country from Mexico.