Leaf spots may be a problem especially in wet years, but they usually don't affect the first bloom. Cut plants back severely after flowering and the new growth will be strong and healthy. The only disadvantage of coreopsis is the necessity of deadheading. Trim spent flowers off regularly to promote continuous production of new flowers. If not deadheaded, only naked flower stalks will remain above the foliage.
Propagation is accomplished through seed, cuttings, or division.
Named cultivars should be propagated vegetatively rather than through seed to ensure true identity. Coreopsis can also be used as fresh cut flowers, especially those with long flower stems. At the end of the flowering season, allow seeds to remain for the birds to enjoy. Not many plants offer season-long beauty, both indoors and out, and also provide food for our feathered friends. Coreopsis is a highly valued perennial for many garden settings.