Many rose growers like to import roses that are not available in the United States, such as new European varieties. Before you can import roses from countries other than Canada, you must obtain permission from the U.S. Department of Agriculture.
To begin the process, write to the USDA for the necessary permit forms (Permit Unit, USDA, PPQ, Federal Building, Room 638, Hyattsville, MD 20782). After you fill out and return the forms, a USDA inspector will visit your garden to make sure that you have an area where you can grow the roses in quarantine; this area must be located at least 3 meters (about 10 feet) away from the rest of your rose garden.
After the inspector approves the forms, you will receive separate permit tickets to enclose with your rose orders. The vendors must attach these to the plants they ship to you. Once you have received and planted the roses, a USDA inspector will visit regularly to ensure that they are free of foreign insects and diseases. After two years, you will receive a Release from Postentry Quarantine notice, which allows you to move the roses to another area of your garden if you wish.
No permits are needed to import roses from Canada, though not all Canadian rose nurseries will ship to the United States. However, gardeners visiting Canada can drive to these nurseries and bring roses back with them.
Imports from certain other countries are banned from time to time. Check with the USDA for the latest list.