Cooler temps and a fair amount of rain have resulted in an outstanding spring for flowering plants. Many island residents and visitors have commented on the outstanding Oleander display, Orchid Trees, flowering annuals, etc. However – I think we all know the Dog Days of Summer are just around the corner and we’ll soon be down to those flowering plants that can survive Galveston's heat and sparse rainfall.
Periwinkles (Catharanthus roseus) or VInca are among some of our most consistent hot weather performers. There are many different cultivars with a range of colors including white, red, pink, lavender and variations of each. These modern day selections are well adapted to our environment and sold by retail garden centers throughout the area. BUT – the best periwinkles for Galveston Island are those that have re-seeded and through successive generations, reverted back to the parent plants. I’m sure you’ve probably seen them. Usually a lavender color, 8” – 12” tall and often flowering in full sun when everything else is wilted.
In a normal winter (whatever that is lately) periwinkles are not hardy. They freeze to the ground and that’s that. But – the seeds left behind germinate in spring, when soil temperatures warm up, and the cycle starts again. Many savvy gardeners dig up these young seedlings and move them around to get a good distribution of plants throughout a bed area. Some folks just let them come up where ever and enjoy the color. (Note: this past winter was so mild that many plants didn't freeze).
These non-hybrid types (for lack of a better term) seem to be tougher than the modern cultivars – which are often susceptible to diseases, like aerial phytopthora. And they take our hot weather while being among the most drought tolerant flowering plants available.
So how do you get some of these bad boys? Periwinkles transplant pretty easily and you’d be surprised where you may find them (i.e. a crack in the sidewalk). Once they start flowering, seed will form and next spring there’s a good chance seedlings will develop. Just remember where they were so you don’t pull the tiny plants thinking they're weeds.