How to Grow and Care for Cosmos

Cosmos are annual plants with abundance of daisy-like colorful flowers seen on the top of slender stems. The flowers come in attractive colors like red, pink, orange, white, chocolate and yellow. These plants can be easily grown by scattering the seeds. They can survive even in poor soil conditions with no specific desiderata.

Cosmos are gardeners’ favorite plants due to their attractive blossoms and the least maintenance. Cosmos plants can be grown in the borders of garden or in containers. Cosmos sulphureus and Cosmos bipinnatus are usually grown in gardens. Although they grow easily, do provide some optimum conditions for their healthy growth and good blossom.

Light: Cosmos have pretty good blossom in full sun. They can tolerate extreme heat conditions even in partial shade.

Soil: Loose, weed-free soil is preferable for these plants. Dry, arid soil is better for cosmos than too moist soil. Addition of some organic matter gives well-draining soil, promoting a rapid growth of cosmos.

Water: Watering is needed, only when you notice drought. Even though you don't water the plants, they are able to survive in any unfavorable conditions.

Temperature and Humidity: Do check for the risk of frost, before you transplant cosmos outdoors.Their growth may be affected by a late frost. However, their growth is not much influenced by humidity.

Fertilizer: Since cosmos plants can grow well in poor soil conditions, unnecessary fertilization may give negative growth effects. Don't opt for using fertilizers, unless your plant seems to struggle. 

Mulching: Mulching the plant around the base during early spring can help to retain moisture and also prevents the growth of weeds.

Trimming and Pruning: Trimming of the plant encourages new growth and continuous blossom. During the mid-summer, you can trim the branches along with removing the blossoms.

Removal of dead or faded flowers is necessary for prolonged blossoms, enhanced flower development and improved branching. Staking is necessary for tall cosmos plants. Protect them from strong winds and provide them necessary support to encourage balanced branching. Water the plants regularly, but avoid over-watering and over-fertilization.

Most varieties of cosmos are short-lived annuals. Once seeds are produced, they don't bloom. You should leave a few flowers on the plants in order to harvest more seeds, because they tend to self-seed.

You have to protect the plant from pests and diseases. Some of the common pests are stem canker, gray mold, aphids and powdery mildew.

It produces dark reddish flowers, having a chocolate scent. Chocolate cosmos plants are grown in containers and at the borders. They are easy-to-grow good cut flowers. They require moist, but well-drained and fertile soil for better growth. However, frequent watering and fertilization is not preferable.

Cosmos are traditionally known to be used in Mexico and Brazil for the treatment of malaria. Cosmos flowers are used in an infused oil as a topical ointment.

Butein in cosmos plant is known for its antioxidant and anti-inflammatory properties. The plant also contains quercetine, which imparts antiviral properties.