These come in a number of flower colors. May 1st is the recommended planting date for periwinkles in Baton Rouge. Periwinkles planted earlier are prone to root rot problems due to cool soil temperatures. A well-drained raised bed in full sun is needed for periwinkles. Recommended pH is 5.4-5.8.
Periwinkles can perform very well in the landscape with little irrigation.
Mulch with pine straw or a similar material to prevent splashing of soil up onto the foliage - this minimizes disease problems. In May, you can also continue planting some additional warm season bedding plants. Keep in mind that it is important to remove faded flowers on marigolds, salvia, and some other warm season bedding plants to encourage re-bloom. Similarly, keep coleus pinched back every 3-4 weeks to produce more foliage, slow flowering, and develop a more compact plant. Bulbs May is the recommended month to plant caladiums.