Threadleaf Coreopisis 'Zagreb', aslo known as Whorled Coreopsis 'Zagreb', is a fine leafed beauty growing uniformly to about 20" tall blooming in late May-June with sunny yellow flowers. This is a lovely landscape specimen. 
 
Coreopsis verticillata 'Zagreb' will spread slowly by rhizome to about 2' wide. It is a well behaved plant for the front of a border and is charming planted in groups. They attract butterflies and a variety of pollinators. Birds eat the seeds.
 
This plant is deer, drought and salt tolerant. It holds up well to heat and humidity.