Annuals & Perennials–which grow back every year, and
can Dimorphotheca plant grow in sandy soil?
Certified GKH Gardening Expert
It would seem that they are more suited for clay soils, but they should be able to tolerate sandy soil types. This article will give you more information on the care of these: https://www.gardeningknowhow.com/ornamental/flowers/cape-marigold/growing-cape-marigold-annuals.htm