Joan Senior is probably my favorite daylily - and that's saying a lot since I love many of them. It starts blooming mid-season (late May here) and keeps blooming deep into summer and early fall.
The plant puts out scapes of flowers that are quite tall - to 3' high. There are plenty of blooms too. This particular plant has not received much water during our drought conditions, so it looks somewhat spindly.
The blooms are a delectable cream color with a lime-green throat. This color goes well with almost any other color making this a perfect daylily for the mixed perennial bed.
This is an evergreen daylily, which is another thing in its favor for the Deep South. The flowers can get up to 6" across.
Another nice thing about these blooms is that they have a mild, but sweet fragrance. This daylily has been around since the 70's and has always been one of the most popular. As with all daylilies, plant this one in full sun or part shade in nearly any type of soil. It needs virtually no care at all to thrive. Daylilies are truly wonderful plants for those who have a "black" thumb. They will grow anywhere from zone 4 and southward. Be aware that rabbits and deer both munch on daylilies on occasion.