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The clear crisp flowers and glossy green leaves of annual vinca are so perfect you may be tempted to rub them to see if they are real. Annual vinca, occasionally called periwinkle, is not related to the perennial ground cover with the same common name. In fact, annual vinca is native to Madagascar and is prized for its nonstop flower show from early summer till fall. Annual vinca is drought tolerant and requires almost no maintenance to keep it looking terrific. Use it en masse in beds and borders or tuck it into mixed containers with other annual flowers. Annual vinca grows 12 to 18 inches tall and comes in pink, purple, red, white, magenta, and bi-colors. The flowers are also attractive to butterflies. Hardy in zone 10.

Annual vinca doesn't require deadheading, or the removal of faded flowers, to continue blooming, making it a wonderfully low-maintenance annual flower for sun. Some older types of vinca can self seed in the garden, especially in subtropical areas. It can be invasive in certain areas; check local restrictions before planting it.

Images source: google
Contents source: http://www.costafarms.com/plants/vinca-annual