WSU Clark County Extension
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Threadleaf Coreopsis

Scientific name: Coreopsis verticillata ‘Zagreb’
Taxonomy
Family:Asteraceae
Type:Herbaceous perennials
Native:NO
Plant Requirements
Zone:5 to 10
Sun:Full sun
Moisture:Dry
Plant Characteristics
Height:1 ft
Width:2 ft
Bloom:Summer flowers
Bloom Time:June to October
Bloom Color:Yellow
Additional Characteristics
Trees


Fruit

Leaves


Bark
Wildlife value

Poisonous
Description Thread-leaved Coreopsis is best known for its feathery foliage and gorgeous greenish-yellow flowers. Also known as Whorled Tickseed.

Thread leaf coreopsis is very tolerant of drought, poor soils, heat and neglect and will flatter you with happy yellow flowers all summer long even if you don't deserve them!

  Morphology:
Threadleaf Coreopsis is a bushy, yet elegant, much-branched herbaceous perennial with three-parted threadlike leaves arranged in opposite pairs or in whorls of three. Mature plants of the ‘Zagreb’ cultivar grow to 1’ by 2’. This cultivar spreads slowly by thin underground stems (rhizomes) and is self-seeding, particularly in moist fertile soils.

Flower heads are about 2” across, consisting of both ray and disc florets which are yellow. Flowers are produced abundantly in loose, open clusters on thin, wiry stems in early summer until first frost.

Honeybees and butterflies appreciate the copious nectar produced by these pretty yellow daisies.

  Adaptation:
This cultivar is easily grown in dry to medium wet, well-drained sites in full sun. It will also survive on poor, sandy or rocky soils with good drainage. It will tolerant heat, humidity, and drought. This cultivar tends to sprawl, particularly if grown in moist and/or fertile soils.

  Pests:
No serious insect or disease problems.
For assistance, contact Dr. Charles Brun (brunc@wsu.edu), (360) 397-6060 5701
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