Mandevilla is the mailbox vine of the moment. This twining, woody tropical vine is sold at garden shops in pots and is grown as an annual. The lush, cheerful flowers are up to 4 inches across. They're big enough make an impression at the curb, even if the traffic is going by at 35 miles per hour, but the vines are well mannered and do not threaten to engulf the mail carrier. Compact new cultivars in the Vogue series are pretty in hanging baskets.
Mandevilla vines may grow to 20 feet or more in southern Florida, where they are winter-hardy, but they remain smaller in more temperate areas or when grown in pots. Gardeners at the Missouri Botanic Garden in St. Louis note that container-grown mandevillas climb 3 to 5 feet. At the end of the gardening season, cut them back and move the plants to a sunny room indoors; return them to the garden after the danger of frost is past in spring.
Illustrations: Elara Tanguy