Edward F. Gilman and Teresa Howe2
Often known as Vinca rosea, Vinca multiflora, periwinkle grows 7- to 24-inches-high and broad, forming a mound of colourful flowers in white, pink, or rosy-purple on brittle stems (Fig. 1). Cultivars can be found with carpet-like or upright habits. Flowering is prolific all through the nice and cozy months, though crops might set up poorly in highly regarded climate. The plant tolerates warmth and flowers within the hottest climate, most likely higher than most different flowering floor covers. Spaced 12- to 20-inches-apart, crops will type a strong mass of mounded foliage and flowers 6- to 8-weeks after sowing seed, supplied they’re fertilized, watered flippantly (or in no way), and planted in full solar.
Scientific identify: Catharanthus roseus
Pronunciation: kath-uh-RANTH-us ROE-zee-us
Widespread identify(s): periwinkle, vinca, Madagascar periwinkle
Plant kind: annual; perennial; herbaceous; floor cowl
USDA hardiness zones: 9B by 11 (Fig. 2)
Planting month for zone 7: Jun
Planting month for zone 8: Might; Jun
Planting month for zone 9: Apr; Might; Jun; Sep; Oct
Planting month for zone 10 and 11: Feb; Mar; Apr; Might; Sep; Oct; Nov; Dec
Origin: not native to North America
Makes use of: edging; floor cowl; mass planting; naturalizing; hanging basket; cascading down a wall; border
Availability: typically out there in lots of areas inside its hardiness vary
Peak: 1 to 2 toes
Unfold: 1 to 2 toes
Plant behavior: spherical
Plant density: reasonable
Development price: reasonable
Leaf association: reverse/subopposite
Leaf kind: easy
Leaf margin: complete
Leaf form: elliptic (oval)
Leaf venation: pinnate
Leaf kind and persistence: deciduous
Leaf blade size: 2 to four inches
Leaf colour: inexperienced
Fall colour: not relevant
Fall attribute: not relevant
Flower colour: pink; purple; lavender
Flower attribute: year-round flowering
Fruit form: pod or pod-like
Fruit size: .5 to 1 inch
Fruit cowl: dry or exhausting
Fruit colour: inexperienced
Fruit attribute: inconspicuous and never showy
Trunk and Branches
Trunk/bark/branches: not relevant
Present 12 months stem/twig colour: inexperienced
Present 12 months stem/twig thickness: medium
Gentle requirement: plant grows partially shade/half solar
Soil tolerances: clay; sand; acidic; barely alkaline; loam
Drought tolerance: excessive
Soil salt tolerances: unknown
Plant spacing: 12 to 18 inches
Roots: not relevant
Winter curiosity: plant has winter curiosity as a consequence of uncommon type, good persistent fruits, showy winter trunk, or winter flowers
Excellent plant: not significantly excellent
Invasive potential: might self-seed annually
Pest resistance: very delicate to a number of pests or ailments which might have an effect on plant well being or aesthetics
Use and Administration
Periwinkle will cascade over a wall or container and makes a pleasant hanging basket. Derivatives from periwinkle are utilized in a wide range of medicines and coverings for human illnesses together with leukemia and hodgkins illness. Crops seed themselves into the panorama.
The plant requires full solar and has an extended rising interval. Periwinkle likes to be stored on the dry facet and the roots will rot if irrigated too regularly. It’s best to not irrigate periwinkle greater than two or thrice after it’s planted. As soon as summer season rains start, crops usually succumb to root rot ailments from an excessive amount of water. A mattress of periwinkle seems to be nice till this time, but it surely ought to often be thought of a brief lived annual. A 3 month interval of colour with out illness is taken into account superb. As soon as crops are eliminated, plant with one other annual to complete the season. Some horticulturists have success rising periwinkle on a raised mattress comprised of sand or different very well-drained soil.
Propagation is by seed or cuttings. Softwood cuttings may be taken and rooted throughout summer season. The seed germinates in a single week at a temperature of 70°F to 75°F. Maintain the flat of seeds at midnight till the seed germinates and don’t overwater. Planting could also be executed at any time in the course of the 12 months in USDA hardiness zones 10 and 11.
There are a number of cultivars out there for flower colour and plant measurement. The ‘Carpet’ and ‘Little’ Sequence develop to not more than 12 inches tall. They too are delicate to root illness.
Pests and Illnesses
No pests are of main concern.
Root rots repeatedly trigger decay of roots and decrease stems.
Fusarium wilt may cause plant demise.
Blight causes brown or black spots which lengthen inward from the leaf edge and finally cowl the entire leaf. Area crops farther aside in subsequent plantings. Take away contaminated crops.
Canker and dieback trigger the shoot tip to turn into darkish brown, wilt, and die again to the soil floor. The illness is most typical throughout wet climate. Contaminated crops ought to be discarded.
A number of fungi trigger leaf spots on periwinkle however they’re often innocent.
U.S. Division of Agriculture, UF/IFAS Extension Service, College of Florida, IFAS, Florida A & M College Cooperative Extension Program, and Boards of County Commissioners Cooperating. Nick T. Place, dean for UF/IFAS Extension.