Appropriate Climate

• Scabiosa are well suited to U.S. Department of Agriculture plant hardiness zones 3 through 7, where cool, humid climates and full sun are preferred for growth. Drooping scabiosa may be symptomatic of the plant's reaction to a less than desirable climate where it is too warm, shady or dry to support appropriate growth.
  
  

Disease and Pests

• According to the University of Florida Cooperative Extension, scabiosa are relatively disease and pest resistant. The University of Vermont Extension does, however, mention that the plant can be bothered by the occasional damaging slug.
  
  

Lack of Water and Nutrients

• The most common of the causes for any drooping flower not affected by disease or pests is the lack of appropriate water and necessary nutrients. Check to see that water is sufficient and that good broad-spectrum plant food has been administered to add any lacking nutrients.