Periwinkle

Periwinkle, also known as vinca, is a tropical perennial that is often grown as an annual. It will flower when only a few inches tall and then grow and bloom until the first frost. The shrubby plant produces many 1- to 2-inch phlox-like flowers, almost covering the glossy, deep green leaves.

Even though the reputation of the Periwinkle has been damaged by a serious disease, it is worth giving this exceptional flowering plant another chance.

Periwinkles have been a great choice for many years in many colors and forms. However, they have seen a dramatic improvement in recent years with new colors, larger plants, and greater plant vigor.

The 1991 All-American Selections has improved that it now includes three new varieties: Pretty in Pink and Pretty in Rose.

Pretty in Pink is the very first pastel pink periwinkle to be introduced. This variety is also a great choice for gardeners to grow plants in containers, hanging baskets, and patio planters. 

It is easy to combine pastel pink flowers with other colors, such as blues or roses. Each flower will measure at least 2 inches in size.

A new color, Pretty in Rose, is a deep velvety rose-purple. It also performs well in hanging baskets, urns, and patio planters, provided that it is exposed to full sun.

Parasol produces a large number of white blossoms, measuring 2 inches in diameter. One All-American Selections judge described Parasol as “a solid mass color all summer” Parasol’s color is very similar to that of the Bright Eyes older variety. However, Parasol’s flower size, vigor, and bloom-producing ability are significantly improved.

Periwinkle Care

Planting too early is one of the main reasons for poor performance in the garden. Periwinkles should not be planted in the spring. They are tropical and can thrive in heat and sun. 

Plants that are planted too soon in cold soil will shiver and become irritated. Planting is best from late May to early summer. The plants will quickly grow when the soil is warm and form a full flowerbed of striking landscape color.

The Austin-based market is also home to older varieties like Little Pinkie and Coquette and Rose Carpet, Rose Carpet, Polka Dot, and Coquette.

You can find periwinkles in nurseries and garden centers throughout Austin and Central Texas. You can find them in either full sun or partial shade. They can thrive in any soil, but they will thrive best when the soil is well-drained. 

Iron chlorosis can cause the leaves to turn yellow in our alkaline soils of Central Texas. Iron chelates and iron sulfate can correct this.

The periwinkle is almost immune to pests and diseases. Once established, it will continue to be a joy throughout the summer. Bright flowers and attractive leaves provide color in a time when few other plants are available.

Periwinkle breeders predict that the periwinkle color will surpass zinnias within the next ten years, and new combinations will match the rainbow.

Madagascar Periwinkle

The Madagascar periwinkle has been a favorite of mine for many years.

It was once known as Vinca rosea, and it continues to do so in many catalogs. But, taxonomists who are always meddling with these matters determined that it was Catharanthus roseus.

It has many virtues, no matter its name, and an unspoken one that gives it a greater significance than the garden.

The periwinkles’ dark green leaves are so shiny that it almost looks like furniture polish. Sometimes, the single flowers are deep pink to pristine white and sometimes have a deeper rosy hue.

They bloom almost continuously and, although they can rot in heavy rain, I have not seen one.

For several years, I have had a large collection of white periwinkles growing in a sunny area next to my driveway of black asphalt. I have rarely had to water the plants despite driveway temperatures reaching 120 degrees in August.

Mildew can attack zinnias, leaving them looking ratty. Petunias can also be prey to blight, but I have never seen a diseased Periwinkle.

Catharanthus roseus is not eaten by insects. Because the plants contain powerful alkaloids used to treat Hodgkin’s Disease and certain types of leukemia, they are exempted from their diet is vincristine or vinblastine.

These flowers are distinctive from all other varieties because they have larger blossoms and overlapped petals. Parasol is a white variety with a dark rose-colored eye. It has large flowers that are about 50 cents.

All three of them are 1991 All American Selection Award winners, which means they have done exceptionally well in all test gardens across the country.

These 14-year-old Catharanthus strains are the first fruits of an ambitious breeding program by Ronald Parker (associate professor of horticulture & plant science at the University of Connecticut).