This naturalizing perennial is drought tolerant and a good choice for restoration or conservation projects.
FIRST IMPRESSIONS: Coreopsis verticillata ‘Zagreb’ is a rhizomatous perennial that grows in compact bushy clumps. Plants have many slender upright stems clothed in pairs of bright green thread-like leaves. In summer stems are topped by multitudes of bright yellow daisies. Plants attain a 1’ height and flourish in sunny or partly sunny sites with dry or mesic soils.
HABITAT & HARDINESS: The parent species Coreopsis verticillata is native to the eastern U. S. from Massachusetts to Florida and west to Arkansas.
The parent species is indigenous to open rocky dry woods, open pineland, margins of woods, pine savannahs and post oak savannahs.
The variety ‘Zagreb’ originated in the Department of Ornamental Plants and Landscape Architecture at the University of Zagreb in Zagreb, Croatia. The cultivar was named in 1997 and was selected for its compact growth, drought resistance and long period of bloom.
Plants are hardy from USDA Zones 3-9.
PLANT DESCRIPTION: Coreopsis verticillata ‘Zagreb’ is an upright and compact selection
Leaves are opposite and very narrow. The blades are parted into 3 thread-like segments. Each blade has a pointed tip and no stalk or petiole. This fine textured foliage gives plants a quality of airiness.
From summer until early autumn plants bear a profusion of 1’ bright yellow flowers. Each of the daisy-like blossoms consists of slender golden ray florets surrounding a yellow cluster of disk florets. Dark colored achene seed form after blooming.
This plant is generally 1’ tall with a 1.5’ spread.
CULTURAL & MAINTENANCE NEEDS: Coreopsis verticillata ‘Zagreb’ is easy to grow in sunny dry or mesic sites. Plants thrive in infertile sandy and rocky soils and tolerate drought, some salt, infertile soil, heat and humidity. If soil is too rich or moist, stems become weak and plants tend to flop.
This selection is said to be tolerant of clay soil and of southern heat and humidity.
Deadheading of spent flowers promotes a fall re-bloom and prevents unwanted seedling volunteers. Most gardeners simply shear the entire plant in late summer to deadhead and neaten matted growth at the same time.
This cultivar is relatively pest free and is also unpalatable to deer and other herbivores.
LANDSCAPE USES: This is a good Groundcover, Accent or Butterfly Nectar Plant for a Meadow or Wildlife Garden. Plants tolerate some salt and drought and can be used in seaside location if there is no direct salt spray. Coreopsis verticillata ‘Zagreb’ has Showy Blooms and is appropriate for Cottage Gardens, Deer Resistant Plantings, Groupings or Mass Plantings, Rock Gardens, Water-wise Landscapes, Low Maintenance Plantings and Perennial Borders.
COMPANION & UNDERSTUDY PLANTS: Try pairing Coreopsis verticillata ‘Zagreb’ with Asclepias tuberosa, Echinacea purpurea and Stokesia laevis.
The parent Coreopsis verticillata or the cultivar ‘Moonbeam’ could be used as stand-ins.
TRIVIA: Coreopsis verticillata ‘Zagreb’ received the Royal Horticultural Society’s Award of Garden Merit in 2001.
Compared to ‘Moonbeam’, the ‘Zagreb’ cultivar has deeper golden yellow blooms, longer blooming time, tolerance to hot dry sites and to heavy clay soils. Coreopsis verticillata ‘Zagreb’ also initiates growth earlier in spring and goes dormant later in autumn than ‘Moonbeam’.