Madagascar periwinkle Catharanthus roseus

Water

Madagascar periwinkle requires moderate watering, and the regimen largely depends on the climate and soil moisture. Water the plant thoroughly when the top inch of the soil feels dry to the touch, which may be about once a week. Adjust the frequency of watering during hotter, drier periods to possibly twice a week, ensuring that the soil doesn't dry out completely. Use enough water to soak the soil to the root level, which might be around 1-2 gallons depending on the size of the plant and pot. During winter, reduce watering to prevent waterlogging, as Madagascar periwinkle is sensitive to root rot in cold, damp soil.

Light

Madagascar periwinkle thrives in full sun but can tolerate partial shade. The ideal spot for this plant is a location that receives at least six to eight hours of direct sunlight daily. If growing indoors, place it near a south-facing window where it will receive ample sunlight to promote blooming. Avoid deep shade locations as this can lead to leggy growth and fewer flowers.

Temperature

Madagascar periwinkle prefers warm temperatures and does not tolerate cold well. The ideal temperature range for this plant is between 65 to 85 degrees Fahrenheit. It can survive minimum temperatures of around 60 degrees Fahrenheit but should not be exposed to temperatures below 50 degrees Fahrenheit as it is not frost-tolerant. During winter or cold nights, it's best to bring the plant indoors or provide protection from the cold.

Pruning

Prune Madagascar periwinkle to encourage bushier growth and more blooms. Cut back leggy stems and spent flowers throughout the growing season to keep the plant looking tidy and to stimulate additional flowering. The best time for significant pruning is in the early spring before new growth begins. Pruning can be done every few weeks or as needed when the plant appears overgrown or untidy.

Cleaning

As needed

Soil

The best soil mix for the Madagascar periwinkle should be well-draining and fertile, with a mix of potting soil, peat moss, and perlite or sand. The pH should be slightly acidic to neutral, between 6.0 and 7.5.

Repotting

Madagascar periwinkle should be repotted every 2-3 years or when it outgrows its current pot, to encourage healthy growth and blooming.

Humidity & Misting

Madagascar periwinkle prefers moderate humidity levels but is quite adaptable and can tolerate lower humidity conditions common in home environments.

Suitable locations

• Indoor

  Place in bright indirect light and water when topsoil is dry.

• Outdoor

  Full sun to partial shade, well-draining soil, water moderately.

• Hardiness zone

  9-11 USDA

Life cycle

The life of a Madagascar periwinkle begins with seed germination, triggered by warm temperatures and moist soil conditions. Once germinated, the seedling emerges and establishes a root system, followed by the development of foliage as it enters the vegetative growth stage. After vegetative growth, Madagascar periwinkle enters the flowering stage, usually within a few months, producing five-petaled flowers that can be white to pink with a darker center. Following pollination, either by insects or through self-fertilization, the plant develops seed pods that eventually dry and release seeds. These seeds can then disperse to start a new cycle if the environmental conditions are suitable. Madagascar periwinkle is a perennial in warm climates, but it is often treated as an annual in cooler regions where it cannot survive the winter.

Propogation

• Propogation time

  Spring to Summer

• The most popular method of propagation for Catharanthus roseus, commonly known as the Madagascar periwinkle or just periwinkle, is through seed. Propagation time is ideally in the spring as the weather begins to warm. To propagate periwinkle by seed, you would begin by sowing the seeds in a well-draining soil mix, covering them lightly with soil, usually no more than 1/16 inch (about 1.5 millimeters) deep. The soil should be kept consistently moist until germination, which typically occurs within 10 to 14 days. After the seedlings have developed a few pairs of true leaves, they can be transplanted into individual pots or directly into the garden. It's essential to gradually acclimate seedlings to outdoor conditions before planting them out to prevent shock, a process known as hardening off. The young plants will benefit from a location that receives full sun to partial shade and regular watering until they are well established.