Coreopsis verticillata 'Zagreb' (Threadleaf Coreopsis)
Threadleaf Coreopsis 'Zagreb', Whorled Coreopsis 'Zagreb', Coreopsis 'Zagreb', Tickseed 'Zagreb'Coreopsis verticillata ‘Zagreb’, commonly known as Threadleaf Coreopsis, is a compact, herbaceous perennial celebrated for its profusion of bright golden-yellow, daisy-like flowers. Blooming continuously from early summer to early fall, this award-winning plant forms a dense mound of finely divided, thread-like green foliage, adding a delicate texture to the landscape. Its long-lasting blooms and airy appearance make it a favorite for sunny borders, cottage gardens, and naturalized areas.
Native to North America, Coreopsis ‘Zagreb’ thrives in USDA hardiness zones 3–9. It grows to a height of 12–18 inches and spreads up to 18 inches, making it an excellent choice for mass plantings or as an accent in mixed perennial beds. This low-maintenance plant is drought-tolerant, deer-resistant, and highly attractive to pollinators, including bees and butterflies.
Care Instructions for Coreopsis verticillata ‘Zagreb’
- Light Requirements: Thrives in full sun but tolerates partial shade, especially in hot climates.
- Soil Needs: Prefers dry to medium moisture, well-draining soils. It adapts to poor, sandy, or rocky soils but dislikes wet conditions.
- Watering: Water regularly during the first growing season to establish roots. Once established, it is drought-tolerant but benefits from occasional watering during prolonged dry spells.
- Pruning: Deadhead spent flowers to encourage continuous blooming. Shear plants back by one-third in midsummer to promote a fall rebloom and maintain a tidy appearance.
- Fertilization: Apply a balanced, slow-release fertilizer in early spring to support healthy growth and flowering. Avoid over-fertilizing, as this can lead to excessive foliage growth at the expense of blooms.
- Winter Care: In colder regions, cut back foliage to the ground in late fall or early spring. Mulch lightly to protect roots from freezing temperatures.
- Propagation: Divide clumps every 2–3 years in early spring to maintain vigor and control spread.
