Answer: You may be killing your plants with such loving attention! Gaillardia grows best in a spot with full sun; it likes hot, dry weather and tolerates a wide variety of soils. Gaillardia does best where it's hot and dry but not where it's hot and humid. I'd stop using the neem and Sevin (unless you see insects; then identify them and use the least toxic control such as insecticidal soap). Water them deeply once each week and trim off the spent flowers which will encourage additional flowers. Hope this information helps!
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