Vinca Rosea Plants in Southern California

Planting

• Madagascar periwinkle tolerates a range of growing conditions. Providing that the soil drains well, it isn't fussy about soil type and it grows in partial shade or full sun. Months for planting out differ according to USDA zone. In zone 8 areas such as Lancaster, California, for example, Madagascar periwinkle doesn't survive winter, so it should only be planted out in May and June. In Los Angeles, Long Beach and other zone 10 areas, it can go in the garden any month except January, June, July and August because it does not develop well in extremely hot weather. Space plants 12 to 18 inches apart, and water just enough to moisten the ground around the root ball.

Growing

• Limited applications of water and fertilizer are all that Madagascar periwinkle needs to flower beautifully through summer heat. Watering should be kept to a minimum to avoid root rot -- two or three times after planting out is usually sufficient. Spray plant leaves every two weeks with a foliar fertilizer diluted at a rate of 1 tablespoon per gallon of water, or according to the manufacturer's instructions.
  Use containers with drainage holes for growing Madagascar periwinkle, and place large stones or broken pot shards on the bottom of the container for additional drainage.

Diseases

• Disease often kills Madagascar periwinkle before it reaches the end of its natural growth cycle. Inadequate drainage and heavy rainfall cause root rot, which is the most common disease of this plant, causing roots and lower stems to die. Growing on raised beds in sandy soil may prevent this disease. Rainfall also causes canker and dieback, where shoot tips turn dark brown and wilt. Brown or black spots that grow inward from leaf edges are a symptom of blight, which is caused by plants growing too closely together. Removing infected plants helps prevent the spread of disease.

Landscaping

• Madagascar periwinkle is a versatile plant. Its relaxed mound of dense foliage makes it an effective ground cover, and it looks attractive cascading down stone walls or from hanging baskets. Its prolific flowers are an asset in borders and when growing as a specimen container plant. As a compact, low-growing plant. it's also suitable for edging borders and walkways. Plants can self-seed in zone 10 areas in Southern California; in some areas, Madagascar periwinkle is considered invasive.