Alphabetical Plant Listing

Cosmos Flowers

Mexican Aster, Orange Cosmos, Yellow Cosmos, Cosmos bipinnatus, Cosmos sulphureus, Sulphur Cosmos, Cosmos atrosanguineus, Chocolate Cosmos (Cosmos)


With finely cut leaves, showy flowers, and a long blooming season, Cosmos are half-hardy annuals or perennials blooming profusely from early or midsummer until fall, depending on varieties. Ridiculously easy to grow, fairly pest-free, and low maintenance, they attract birds, bees, and butterflies to your garden. They are grown in borders, in containers, and for cutting. They make excellent cut flowers thanks to their long vase life and richly colored petals which compliment any bouquet.

Native to Mexico, most of the cosmos we grow derive from three species:

Cosmos atrosanguineus (Chocolate Cosmos)

Highly sought after, Cosmos atrosanguineus are half-hardy, tuberous perennials boasting chocolate-scented, velvety deep crimson flowers, up to 2 in. across (5 cm), from midsummer to fall. Their pinnately divided leaves are often lobed at the base and are attached to the stems by winged petioles. These profuse bloomers create a striking visual impact in the garden and look particularly outstanding when combined with ornamental grasses. They are also ideal in containers where their fragrance can be enjoyed.

Cosmos atrosanguineus

Cosmos atrosanguineus Chocamoca

Cosmos bipinnatus (Mexican Aster)

True eye-catchers, Cosmos bipinnatus are bushy, half-hardy annuals boasting single, semi-double, or double daisy-like flowers, as large as 5 in. across (12 cm), in a wide array of colors including pink, white, red, and bicolor varieties. Blooming for months from early summer to fall, the ravishing blossoms are borne atop branching stems and float above the fine, feathery foliage. Ranging from 2-5 ft (60-150 cm), tall varieties are ideal towards the back of mixed borders or in a row for cutting, while smaller cosmos varieties are perfect for the patio and terrace or at the front of borders.

Guide Information

Hardiness 2 - 11
Heat Zones 1 - 12
Climate Zones 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 1A, 1B, 2A, 2B, 3A, 3B
Plant Type Annuals
Plant Family Cosmos
Exposure Full Sun
Season of Interest Summer
Fall
Water Needs Average
Maintenance Low
Soil Type Chalk, Loam, Sand
Soil pH Acid, Alkaline, Neutral
Soil Drainage Moist but Well-Drained, Well-Drained
Characteristics Cut Flowers, Showy
Attracts Butterflies, Hummingbirds
Landscaping Ideas Beds and Borders, Patio and Containers
Garden Styles City and Courtyard, Cutting Garden, Traditional Garden

Pictures are courtesy of National Garden Bureau, Benary, Botanik Foto, sakurai_dayo

While every effort has been made to describe these plants accurately, please keep in mind that height, bloom time, and color may differ in various climates. The description of these plants has been written based on numerous outside resources.

Guide Information

Hardiness 2 - 11
Heat Zones 1 - 12
Climate Zones 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 1A, 1B, 2A, 2B, 3A, 3B
Plant Type Annuals
Plant Family Cosmos
Exposure Full Sun
Season of Interest Summer
Fall
Water Needs Average
Maintenance Low
Soil Type Chalk, Loam, Sand
Soil pH Acid, Alkaline, Neutral
Soil Drainage Moist but Well-Drained, Well-Drained
Characteristics Cut Flowers, Showy
Attracts Butterflies, Hummingbirds
Landscaping Ideas Beds and Borders, Patio and Containers
Garden Styles City and Courtyard, Cutting Garden, Traditional Garden
Not sure which Cosmos to pick?
Compare All Cosmos
Great Plant Combination
Ideas with Cosmos
Guides with Cosmos

Find your Hardiness Zone

Find your Climate Zone

Find your Heat Zone

Join Gardenia.net

Create a membership account to save your garden designs and to view them on any device.

Becoming a contributing member of Gardenia is easy and can be done in just a few minutes. If you provide us with your name, email address and the payment of a modest $25 annual membership fee, you will become a full member, enabling you to design and save up to 25 of your garden design ideas.

Join now and start creating your dream garden!

Create a New Collection

Optional. For your reference.


Move Selected Plants to a Different Collection


Delete Collection

This field is required.

Rename Collection

This field is required.