Sylvester Threadleaf Tickseed

Sylvester is a named selection of Coreopsis verticillata with yellow ray flowers, fine divided foliage, and an upright bushy to rounded habit. Ball Seed lists mature dimensions of 16–20 inches tall by 14–16 inches wide and hardiness in Zones 5a–9b. The Canadian Food Inspection Agency’s cultivar record identifies the denomination and species, and describes Sylvester as shorter and smaller-flowered than the comparison cultivar Zagreb. [CFIA](https://active.inspection.gc.ca/english/plaveg/pbrpov/cropreport/core/app00008996e.shtml) ## Landscape Use Use this compact perennial in sunny borders, edging, or grouped plantings where its fine texture and yellow summer flowers can be appreciated. Its modest spread suits smaller garden spaces, while the mounded form softens the front of a mixed border. ## Growing Conditions Plant in full sun and ordinary, well-drained soil. Ball Seed recommends medium watering and reports flowering in summer, with additional seasonal bloom possible in suitable conditions. USDA hardiness sources list Zones 5–9; local performance depends on exposure and winter drainage. ## Maintenance Water through establishment and during prolonged dry weather. Trim spent flowers or shear lightly to refresh the plant; remove old stems as new growth appears in spring. Ball Seed lists patent PP24,767. The dramatic claim that flowers are twice the size of other threadleaf coreopsis is excluded because the official cultivar comparison describes its flowers as smaller than Zagreb’s. [Ball Seed](https://ballseed.com/Products/018900001028200/coreopsis-sylvester)