Are Your Periwinkles In Peril?
Do you have Periwinkles in your landscape that seem to be diseased or suffering and dying? There are several soil borne diseases that attack Periwinkles when conditions are favorable. Pythium and Arial Phytopthera are two of the common diseases but there are several others that can have an impact in this area. Weather, repeated use of soil, extreme temperatures, varied amounts of rain and timing make a big difference in their success or total failure in your garden.
Signs and Symptoms
It will be obvious that your Periwinkles are suffering, but the symptoms are often confusing. At first the plants appear dry and wilted so we add more water. (Wrong- that is the worst thing we can do) Then they might start to appear fried or burnt. Once it reaches this stage they are goners. Below you will see pictures of Periwinkles from the same flower bed. Half of the bed is thriving while the other half is mostly dead or dying. This reason for this is tough to explain…there is really no good explanation for it.
Disease Resistant Periwinkles
There was a time in the recent past when Periwinkles were hard to come by. They are very prone to most of the diseases and viruses that they get exposed to in this area. However, we love them here because they love the heat and do very well when properly planted and maintained. Many nurseries and landscapers gave up on them after years of fighting the diseases. Then the “Cora” series was introduced into the market as a more disease resistant strain and our summers the past several years was ideal, HOT – DRY and little if any rain. It seemed like the ideal Periwinkle for our area and we were good to go. Mother Nature had other plans though and the spring of 2014 came around: milder, cooler, rainier and wetter. Not ideal.
Tips and Tricks
The following tips may be useful with beds already infected and preventing it in the future.
- Periwinkles should be rotated throughout flower beds much like farmers rotate their crops from year to year. Planting them in different places each year will help to slow down and/or prevent soil spread diseases.
- Don’t plant them too early! North Texas is notorious for late frosts once Spring has already gotten going. Enduring a few more weeks without color before putting them in the ground. Trying to plant them in March or April because they love our summers is bad news when we have a cool wet spring like this year. They want it HOT and DRY not cool mild rainy springs like we had this year.
- Even though the Cora series is the most resistant it is not disease proof. If you have a bed that is partially infected and want to save the healthy ones, add a good layer of mulch to keep the soil from splashing during rain or irrigation into the dirt and spreading the infection to the remaining healthy plants.
For more tips and information about any of the flowers that you like to grow at your home, please visit The Flower Ranch.
The Flower Ranch, 901 S. Pearson Lane, Keller, Texas 76248