How to Plant, Grow and Care For Coreopsis Flowers

Coreopsis is a diverse group of flowering plants in the Aster family. This genus includes annual and perennial varieties commonly referred to as tickseed. There are over 70 species of coreopsis, at least half of which are native to the United States. In the wild, they grow along roadsides and in open fields, meadows, and pastures. Most have very showy simple flowers in shades of yellow, orange, and red.

For home gardeners, coreopsis is a treat. They are readily available, easy to grow, and beautiful. They are easy to start from seed, young plants, or divisions from larger clusters. Coreopsis thrives in full sun with well-drained soil. In ideal conditions, many varieties will self-seed in the garden, keeping their population strong.

Coreopsis is a group of widespread plants native to North America, including Canada, the United States, and Mexico. Other species are native throughout Central and South America. They grow wild along roadsides or in fields, meadows, prairies, grasslands, and open woodlands.

Coreopsis is a large genus of plants in the Aster family. There are over 70 species of coreopsis and many cultivars as well. The cultivars are not necessarily “better” than the native varieties, just different, with different attributes and a wider assortment of colors. Growers continue to develop new cultivars of these popular plants.

Several native species have become popular as cultivated garden plants. They are easy to grow, easy to propagate, and hardy in the home landscape. The beautiful flowers are showy and attract butterflies. They also make nice cut flowers and are frequently used in ‘wildflower’ bouquets.

Cultivation

When growing a butterfly garden, pollinator garden, cottage garden, or having a sunny plot for a naturalized wildflower garden, there is a coreopsis to meet your needs. There are taller plants to grow in the background, compact varieties to grow at the edge of your plot, and medium-sized plants to nestle among other garden flowers.

Coreopsis includes annual and perennial varieties, although many people opt to grow them all as annuals. Even starting from seed, the plants grow quickly and can bloom in their first year. It is common to see these species in seed mixes for wildflowers, butterfly gardens, and prairies. Anyone can grow and enjoy coreopsis, whether new to gardening or with many years of experience with plants. 

Propagation

Coreopsis is very easy to grow and establish in the home garden. Seeds are readily available commercially, you can collect seeds from someone else’s plant or start with young purchased plants or newly divided colonies. Each method listed below is simple and usually successful in establishing a new plant or flowering patch!

Seed

Starting flowers from seed is an excellent way to save money and practice gardening on a budget. You can generally buy dozens of seeds for the same price as a single young plant. Growing from seed also offers more options to the adventurous gardener.

Fortunately, starting from seed is very simple. The most difficult step may be choosing the variety you want to grow! You can start seeds indoors in pots or outdoors directly sown in the garden.  Loosen the soil, but do not cover the seeds with soil as they need light for germination.

If you start seeds indoors, sow them in fresh, loose, seed-starting soil 6 to 8 weeks before the average last frost in your area. To jump-start your seeds, use a seed-starting heat mat to keep them warm and help them sprout faster. Keep the soil warm and moist (if you use a heat mat, keep a close eye on the soil so it doesn’t dry out!). Seedlings should sprout in about two weeks. 

When starting seeds outdoors, direct sow them into the garden or intended growing container after the average last spring frost. Keep the soil moist until the seeds germinate, which may take 2 or 3 weeks.

Seedlings and Young Plants

When you have seedlings that you grew yourself or have purchased young nursery-grown plants, transplant them into the garden after the danger of spring frost. While selecting a plant to buy, look for fresh, vigorous, and healthy plants.

Avoid plants that appear wilted, mushy, diseased, or infested with insects. You will have the best luck starting with a healthy plant, and you certainly do not want to introduce any new problems to your garden.

Prepare your planting site by loosening the soil. Dig a hole deep enough to accommodate the entire root mass of your potted plant and carefully transfer the plant into the hole.

Add enough fresh soil around the roots to completely cover them and gently tamp down the soil to secure the plant in its new home. Give it a thorough watering to help reduce transplant shock and keep it watered for a few weeks to give it a chance to get established.

Division

Another great option for starting coreopsis is the division of existing mature clusters. If you have a gardening friend or neighbor who grows this plant, or if you already have your own, you can divide these clumps into smaller bunches that you can transplant into new locations. Each smaller bunch can grow, multiply, flower, re-seed, and mature in its new space.

It’s best to divide existing clusters in early spring or late fall. Choose a cool and overcast day, and water your plants well after dividing them.

Use these simple techniques to minimize transplant stress for the best outcome. Generally, plants will look a bit wilted for a few days after transplanting, but they should perk up again as long as you give them some extra water.

Planting

You don’t need anything fancy to plant your new seedling. All you need is a sunny plot in your garden with well-drained soil. If you are adding a few new plants to your garden, the only tool you really need is a trowel and perhaps a pair of gardening gloves. 

The best time of year to do any new planting is early spring. Fall is also a great time for planting perennials.

How to Grow

This native wildflower is remarkably easy to grow if you pick its location wisely.

Sunlight

Coreopsis loves the sun. They should receive at least 6 to 8 hours of direct sunlight each day. Plants grown in the shade will probably appear weaker and not bloom well, if at all. A little dappled afternoon shade, especially in hotter climates, should be fine.

Water

This North American native needs dry to medium moisture soil. Once established, these wildflowers are quite drought-tolerant. Water plants well at the time of transplanting and a few days after. During periods of prolonged drought, they may appreciate an occasional light watering.

Soil

Soil should be well drained. It does not need to be particularly high-quality or nutrient-rich. This plant can thrive in poor soil conditions as long as the soil is well-drained. These plants will not do well in heavy clay soil or waterlogged soil. 

Climate and Temperature

Coreopsis will grow well in USDA climate zones 4 through 9. Most varieties thrive in heat and humidity. These plants tend to be tolerant of a variety of environmental conditions and can be grown in most gardens.

Annuals will die after the first hard frost. Perennials will die back to the ground, but if the roots are not waterlogged over the winter, they will regrow in the spring.

Fertilizer 

One great thing about growing native wildflowers is that they can survive neglect. You will not need to fertilize these plants. You will also not need to spend extra money on soil enhancements unless you want to add some sand to help improve soil drainage.

Maintenance

If you allow your coreopsis to naturalize in your garden, they are very low-maintenance. Expect to do an annual thinning and dividing to keep your plants well-managed. You can reduce self-seeding by deadheading spent flowers. However, with prolifically blooming plants, this task can be rather time-consuming. 

After the foliage dies back in the fall, remove the dead foliage. If you have clusters of plants that overgrew their space, you can divide and thin larger colonies.

This can help keep them more contained and also help improve vitality. If plants get large and scraggly by mid-summer, cut them back severely, and they will regrow in a bushier form.

Garden Design

Coreopsis can be used in many garden situations. Grow them with other annuals or perennials, use them in a pollinator garden, or even grow them in containers. Coreopsis plants are a versatile addition to the landscape and can be enjoyed throughout the growing season. 

Plant taller coreopsis towards the back of a garden plot where their height will be appreciated, and they won’t block smaller plants. Grow smaller sprawling coreopsis varieties along edges and borders where they can be seen and have the most impact.

Many varieties of coreopsis have brightly colored flowers and attractive foliage, so you can use them as decorative flowering plants and long-season foliage plants. 

Varieties

There are far too many varieties to list them all here. There are more than 70 species of coreopsis and many more hybrids and cultivars. Not all species are commercially available, but you should be able to find a few varieties to try, especially if you are willing to grow from seeds. A few of the more common varieties are listed here.

Lanceleaf Coreopsis (C. lanceolata)

Lanceleaf coreopsis has long thin leaves. The cheerful dark-yellow flowers bloom in late spring and early summer atop tall stems reaching 2 feet tall. This perennial wildflower has a broad range across central and eastern North America. 

Large Flower Tickseed (C. grandiflora)

Large-flowered tickseed grows to 2.5 feet tall. This herbaceous perennial is native to eastern and central North America. The flowers bloom throughout the summer and are big, bold, and intensely yellow.

Ear-leaved Tickseed (C. auriculata)

This coreopsis is fairly low-growing, staying less than 1.5 feet tall. It is a perennial native to the eastern United States. This species has broad, oblong leaves and spreads by stolons, creating dense colonies. The large deep-yellow flowers bloom in late spring until early summer.

Threadleaf Coreopsis (C. verticillata)

Threadleaf coreopsis is a perennial wildflower native to the eastern United States. The very thin, feathery leaves add an appealing leafy texture to the garden. The bright yellow flowers bloom from late spring until early fall. 

Red Elf Coreopsis (C. ‘Red Elf’)

‘Red Elf’ coreopsis is a bit different. This perennial plant stays very compact, reaching only about 1 foot tall. Its dark red flowers have prominent yellow centers and bloom throughout summer. 

Plains Coreopsis (C. tinctoria)

The plains coreopsis is an annual wildflower native to the eastern and central United States. This beautiful plant reaches up to 4 feet tall. It has thin, feathery leaves and produces an abundance of golden-yellow flowers with deep burgundy-red centers. Flowering occurs from early summer through early fall.

Wildlife Value

Coreopsis has a well-deserved place in a wildlife-friendly garden. If you find a coreopsis variety native to your area, it can be a huge benefit for local wildlife.

Coreopsis is a great plant for attracting beneficial insects and pollinators. Butterflies and bees love the flowers and visit frequently during the blooming season. After blooming, the mature seedheads will attract hungry birds.  Deer typically do not bother coreopsis, although rabbits will nibble it.

Pests and Diseases

These plants are generally very hardy and vigorous. They are not bothered by many pests and diseases. It’s possible that you may see a few aphids or mealy bugs on your plants, but these insect pests rarely do much, if any, noticeable damage to coreopsis.

Three of the most common problems you will likely encounter are root rot, sunscald, and powdery mildew, which are caused by or influenced by environmental factors.

Root Rot 

Root rot and crown rot can occur if plants are grown in wet or poorly-drained soils, as these conditions provide the perfect habitat for fungal pathogens to thrive in. Coreopsis cannot tolerate constant wetness.

If your plant develops a case of fungal root rot, the entire plant will wilt, become soft and mushy, and eventually die. Root rot can be prevented by growing your coreopsis in loose, sandy or gritty, well-drained soil, as better drainage and loose soil reduces the likelihood of fungal development.

Sunscald

Coreopsis plants are generally quite tolerant of hot and sunny conditions. It is possible, however, for plants to develop sunscald. This can occur in prolonged or extreme heat and drought.

The leaves will brown around the edges or can develop tan or brown splotches throughout. Remove damaged foliage to improve plant appearance. Sunscald is unsightly but rarely affects or kills the entire plant, but if much of the plant is impacted, it can reduce photosynthesis.

Powdery Mildew 

If you notice the leaves of your coreopsis are turning a grayish-white color or look powdery, your plant may have a case of powdery mildew. This generally happens in warm, humid conditions, particularly with poor air circulation.

Powdery mildew is a fungal growth that thrives in high humidity and can affect many species. To prevent powdery mildew, improve the air circulation around your plant.

Do not water overhead; instead, water only at the base of the plant, as wet leaves can catch and trap airborne fungal spores. Remove any leaves that start to develop a powdery, whitish look before they produce more spores that can spread.

Frequently Asked Questions