Vinca (Catharanthus roseus) has flowers that are red, lavender, white, peach or pink. It blooms from spring to fall with glossy, green leaves. Vinca grows 8 to 18 inches tall and spreads up to 1 foot wide. It is commonly used in flower beds and containers. Vinca is a native perennial in Madagascar, but acts as an annual in North America.
Sow vinca seeds in a tray of soil indoors 10 to 12 weeks before the last spring frost. Do not over water the seeds. Vinca seeds germinate in 1 to 2 weeks. Once they are 3 inches tall, transplant them into individual 2 1/2 inch pots. Keep the seedlings inside until the outside weather is consistently above 65 degrees F.
Look for bright green foliage when buying bedding plants. Avoid plants with yellowing leaves since it is an indication of root rot. Look for compact, well-branched plants.
Plant your seedlings in full sunlight after the outside temperature haS warmed up. Mix 1 inch of compost to a depth of 6 inches in a prepared bed before planting. Make sure the soil drains well, since too much water promotes root rot.
Spread mulch around your new transplants to the depth of 1 inch. Use shredded bark or wood chips to minimize water splashing onto the plant leaves. Mulching conserves water and reduces weed growth.
Water the vinca very infrequently since it likes dry soil and is drought tolerant. Correct watering prevents most fungal diseases like root rot and botrytis. Apply the water directly to the soil and do not sprinkle on the foliage. Do not water unless the soil is nearly bone dry.