Plains coreopsis (Coreopsis tinctoria) is an annual flowering plant common to Canada, the United States, and China. Plains coreopsis grows along roadsides and agricultural fields. Plains coreopsis is cultivated in gardens and prefers well-drained sandy soils. The blossoms can be made into mahogany dye.
I. Appearance and Characteristics
Plains coreopsis, garden tickseed, golden tickseed, or calliopsis, Coreopsis tinctoria, is an annual forb. The plant is common in Canada (from Quebec to British Columbia), northeast Mexico (Coahuila, Nuevo León, Tamaulipas), and much of the United States, especially the Great Plains and Southern states where it is often called “calliopsis”. The species is also widely cultivated and naturalized in China.
It often grows in disturbed areas such as roadsides and cultivated fields.
Growing quickly, Coreopsis tinctoria attains heights of 30–100 cm (12–40 in). Its leaves are pinnately-divided, glabrous and tend to thin at the top of the plant where numerous 25–40 mm (1–1+1⁄2 in) flower heads sit atop slender stems.
Flower heads are brilliant yellow with maroon or brown disc florets of various sizes. Flowering typically occurs in mid-summer. The small, slender seeds germinate in fall (overwintering as a low rosette) or early spring. Ray florets have notched tips. Its native habitats include prairie, plains, meadows, pastures, savannas, roadsides, and pond banks. The Latin specific epithet tinctoria refers to its use in dyeing.
Coreopsis tinctoria is pollinated by a wide variety of insects, including long-tongued bees, short-tongued bees, wasps, flies, butterflies and beetles. Coreopsis tinctoria serves as a larval host plant for various insects, such as Synchlora aerata, Tornos scolopacinarius and Calligrapha californica.
II. How to Grow and Care
Sunlight
Plains coreopsis requires sufficient sunlight and prefers direct sunlight, so it is good for sunny gardens or balconies. To grow indoors, at least 6 hours of sunlight is needed. For maximum blooming, over 12 hours of sunlight is best.
Plains coreopsis can survive in partially-shaded environments. However, excessive shade can result in decreased photosynthetic rate, slow growth rate, produce thin, weak stems, difficulty in branching, and fewer flowers. Your plant will be healthier in a bright place.
Temperature
Plains coreopsis grows on grasslands or plains with a very dry environment. It likes a warm and dry growing environment, though it tolerates occasional wet weather. It grows best between 10 to 30 ℃. Cold temperatures result in slow growth. Sufficient water is required during germination, but adult plants have no special requirement for humidity.
Watering
Originating from North American prairies, plains coreopsis thrives in environments that mimic its native conditions of periodic rainfall and well-draining soil. This species is adept at handling short dry spells, preferring a balance between moisture and drought tolerance. Watering every week will maintain its vitality without over-saturating the roots. As an outdoor plant, plains coreopsis exhibits resilience to varying precipitation patterns and often flourishes in regions where rain supplements routine watering schedules, making it a favorite for temperate climate gardens.
Soil
Plains coreopsis adapts to most soil; some varieties even tolerate dry and rocky soil. However, it prefers moist, loose, permeable, well-drained sandy loam, with a pH value of 5.5-6.5. Add a permeable and loose medium, such as sphagnum moss and coco coir, to garden soil and organic matter to increase water retention. An example of a culture medium formula is 1/2 coco coir + 1/4 garden soil + 1/4 vermiculite or river sand. NPK fertilizer and organic fertilizer should be added in spring.
Fertilizing
To bolster plains coreopsis’s vibrant blooms and robust growth, utilize high phosphorus fertilizers. Seasonally, apply these at the onset of the growing period and again midseason for continued vitality. An ideal frequency is once every 4-6 weeks, ensuring to follow the manufacturer’s guidelines on quantity. Over-fertilization can lead to foliage at the expense of flowers. During dormancy in cold months, cease fertilization. Novices should start with half-strength recommendations, adjusting as plains coreopsis’s response dictates. Practical tip: Incorporate fertilizer into moist soil to prevent root burn and facilitate nutrient uptake.
Pruning
Plains coreopsis rarely needs to be pruned. In order to promote blooming, prune the terminal bud when it grows to 5 cm. The same should be done again when branches are 10 cm long; remove thin or weak branchlets then too. Pruning withered flowers in time avoids consuming excessive nutrients, and plains coreopsis will bloom again in fall.
Propagation
Plains coreopsis is best propagated through sowing seeds in Spring. This plant is relatively easy to propagate, with successful germination indicated by emerging seedlings. Thin out seedlings to prevent overcrowding and ensure healthy growth.
Transplanting
Transplant plains coreopsis ideally during the refreshing window of early to late spring. Choose a sunny spot with well-draining soil to thrive. Gently tease the roots apart when transplanting if necessary. Enjoy the vibrant beauty it adds to your landscape!
III. Uses and Benefits
- Ornamental uses
Gardens in need of some mass planting but with poor soil will benefit from plains coreopsis. It can thrive in questionable soil quality, and its showy flowers mean that planting it in drifts has huge payoff. Naturalized, meadow, or very informal gardens are also a good setting for this loose and floriferous plant. Cosmos, Geraniums, or Poppies make for striking contrast plantings.
- Other uses
The Zuni people traditionally use the blossoms of the tinctoria variety to make a mahogany red dye for yarn, and, until the introduction of coffee by traders, to make a hot beverage. Women also used an infusion of the whole plant of this variety, except for the root, if they desired a female child.
IV. Harvesting and Storage
Generally speaking, plains coreopsis can bloom twice a year, once in spring or summer and once in fall. Its flowers can be appreciated for a long time. If it is not harvested, it can bloom for as long as one or two months. After harvest, the vase life of a single flower is between three and seven days. Use sharp gardening scissors to cut at the base of the stem, and prune the base of the stem obliquely at 45° to increase the water absorption area. Put it in a vase with clean water.