EASY CARE FOR ZONE 9a – PERIWINKLE / VINCA

Catharanthus roseus or Madagascar periwinkle – these starter plants will quickly fill in to hide the PVC pipe

 

Periwinkle or creeping myrtle qualifies as a Zone 9a easy care plant because most species thrive in our hot, humid summers if it is planted in well-drained soil. It blooms from early spring to first frost. In today’s nurseries, it is usually marked as Vinca but I prefer the old-fashioned name, periwinkle, as it is difficult to teach an old dog new tricks. It generally does not survive frost or freezing weather and does not reseed itself in enough numbers, or early enough in the season, for me to agree it is a perennial. In Zones 10 and 11, it is a woody perennial.

It hails from Europe and Turkey and bees, butterflies and hummingbirds supposedly love it. I’m not sure I remember seeing any such activity from the critter kingdom but my memory got up and left years ago. There are 12 species of periwinkle, some of which are used as ground covers because the trailing stems will root where the stems touch the soil. I discovered this last summer with a miniature flowered version I purchased not knowing it would become a spreading mound.

Vinca minor grows about 6 inches tall with dark green 2 inch leaves and flowers that are blue, purple, or white.

Vinca major is a larger, blue flowering periwinkle with leaves that can be as long as 3 inches with blue flowers that bloom only sporadically during the summer.

Vinca rosea, now known as Catharanthus roseus or Madagascar periwinkle, originated on the island of Madagascar. It forms 6-18” tall and wide mounds with bushy leaves. The flowers are phlox-like in a wide variety of color ranges – hot pink, pale pink, rose, red, white and an amazing dark purple — often with contrasting eye color. My favorite is a hot pink with white eye; second favorite is Solar Apricot. It is widely available in nurseries and should be marked as Catharanthus roseus or Madagascar periwinkle.

 

HOW TO GET YOUR HANDS ON SOME PERIWINKLES

·         The easiest way to acquire periwinkles is to purchase inexpensive starter plants in the spring when they start showing up in the nurseries.

·         Alternatively, seed can be direct sown outdoors in the fall.

·         Plant seeds 12 – 16 weeks before the last frost date and set out the seedlings after that last frost date.

 

PROPAGATION

Given that it already roots its own trailing stems where they touch the soil, you can help it along with simple layering. Scratch the mulch away, lay the stem on the bare soil and press a rock or whatever is handy on top of the stem.

This year, if I remember, I am going to experiment with cuttings in water. It would be nice to have starter stock I didn’t have to purchase.

Late in the season, periwinkle forms seed spikes about an inch long. As these spikes begin to turn brown, bag the spikes with some of those organza bags mentioned in DIY Butterfly House (the post before this one).

 

PROBLEMS WITH PERIWINKLES

You may see cankers at ground level. These are sunken, wound-like lesions.  Most of my flower beds are edged with liriope (lih-RYE-uh-pee), which I call border grass because it’s too hard to pronounce its fancy name. The border grass prevents my seeing ground level problems. If I can’t see it, it doesn’t exist. I can’t keep up with all the yardwork as it is without trying to treat a $1.12 starter plant.

Overhead irrigation may cause brown, circular or oval fungal spots on the leaves.

Periwinkles are also susceptible to die back – it wilts and dies – from a fungal disease. This happened to one of the twelve I purchased a few weeks ago in a multi-pack. I just snatched it out and trashed it. Problem solved.

 

INVASIVE

Periwinkles can be invasive but I have never had a problem with it. You can check this map if you are concerned.