Although this plant isn't frost-hardy, you can grow it as a perennial if you live in USDA plant hardiness zones 9 and above. Collecting vinca seeds from mature plants isn't difficult, but growing annual vinca from seed is a little trickier.
Annual vinca (Catharanthus roseus) is a tropical perennial that is grown as an annual in most regions. It has flowers and foliage that resemble impatiens, but rather than being a shade lover, annual vinca is a perfect choice for sunny locations.
Sow vinca indoors 12-15 weeks before the last frost. Sow seeds in seed-starting formula and cover with 1/8 inch of seed starting formula. Seeds are sensitive to overwatering, keep lightly moist. Seedlings emerge in 14-21 days at 75-78 degrees F.
(As a general rule, most annual flower seeds are viable for 1-3 years and perennial seed for 2-4 years.). . . . .364011235092!]0000000000000009783314145845!]
