AGRICULTURAL AND FARM NEWS Aster yellows is a condition that affects many flowers including not only coneflower, but also asters, chrysanthemum, coreopsis, cosmos, daisy, dianthus, gladiolus, ...

The flowers are the same colour as a daisy, with a yellow centre and outer white ray florets ... There is some effect on the weed when boom-sprayed with 2,4-D ester, but the plant normally regrows.