''Cosmos bipinnatus'', commonly called the garden cosmos or Mexican aster, is a medium-sized flowering

herbaceous plant Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials. Definitions of "herb" and "herbaceous" The fourth edition ...

in the daisy

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Asteraceae,

native Native may refer to: People * Jus soli, citizenship by right of birth * Indigenous peoples, peoples with a set of specific rights based on their historical ties to a particular territory ** Native Americans (disambiguation) In arts and enterta ...

to the Americas. The

species In biology, a species is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of ...

and its varieties and

cultivar A cultivar is a type of cultivated plant that people have selected for desired traits and when propagated retain those traits. Methods used to propagate cultivars include: division, root and stem cuttings, offsets, grafting, tissue culture ...

s are popular as

ornamental plant Ornamental plants or garden plants are plants that are primarily grown for their beauty but also for qualities such as scent or how they shape physical space. Many flowering plants and garden varieties tend to be specially bred cultivars that ...

s in

temperate In geography, the temperate climates of Earth occur in the middle latitudes (23.5° to 66.5° N/S of Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ranges throughout t ...

climate gardens.

Description

''Cosmos bipinnatus'' is considered a

half-hardy Hardiness of plants describes their ability to survive adverse growing conditions. It is usually limited to discussions of climatic adversity. Thus a plant's ability to tolerate cold, heat, drought, flooding, or wind are typically considered meas ...

annual Annual may refer to: * Annual publication, periodical publications appearing regularly once per year **Yearbook **Literary annual * Annual plant *Annual report *Annual giving *Annual, Morocco, a settlement in northeastern Morocco *Annuals (band), ...

, although plants may reappear via self-sowing for several years. The plant height varies from 2-6 ft to (rarely) 9 ft (). The cultivated varieties appear in shades of pink and purple as well as white. The branched stem is usually densely to occasionally occupied by fine, split up, rough

trichome Trichomes (); ) are fine outgrowths or appendages on plants, algae, lichens, and certain protists. They are of diverse structure and function. Examples are hairs, glandular hairs, scales, and papillae. A covering of any kind of hair on a pl ...

s, some specimens are completely hairless. The petiole itself is inconspicuous, winged, 10 (rarely to 15) mm () long, sometimes the leaves are almost

sessile Sessility, or sessile, may refer to: * Sessility (motility), organisms which are not able to move about * Sessility (botany), flowers or leaves that grow directly from the stem or peduncle of a plant * Sessility (medicine), tumors and polyps that ...

. The partial leaves are linear-filiform to narrow linear with a width of 0.5 to 1 (rarely to 1.7) mm (); the tips are pointed, hardened, but not particularly sharp. Its foliage is finely cut into threadlike segments. When flowering, the plant can become top heavy. This problem is alleviated when grown in groups, as the bipinnate leaves interlock, and the colony supports itself. The

achenes An achene (; ), also sometimes called akene and occasionally achenium or achenocarp, is a type of simple dry fruit produced by many species of flowering plants. Achenes are monocarpellate (formed from one carpel) and indehiscent (they do not op ...

become blackish, are smooth or short-bristly. Their shape is spindle-like. They are rounded off into a short, long, but distinctly pronounced rostrum. The inner achenes are up to long, their yellowish beaks are 4 to 5 (rarely to 10) mm () long. A pappus is missing or it consists only of two to three awn-like, large bristles.

Flowers

The very conspicuous cup-shaped

inflorescence An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed ...

s have a diameter of usually 5 to 7 (rarely 8) cm () and contain tongue and tubular flowers, which are surrounded by

bracts In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves. They may be smaller, larger, or o ...

. The outer bracts are usually eight and are ovate to lanceolate-tail-shaped, long, 3 to 5 (rarely 6) mm () wide. The inner bracts are ovate-lanceolate and long. They are translucent with many black stripes and a clear edge up to 1 mm wide, sometimes with yellowish or pink pigments, the tip is

ciliate The ciliates are a group of alveolates characterized by the presence of hair-like organelles called cilia, which are identical in structure to eukaryotic flagella, but are in general shorter and present in much larger numbers, with a differen ...

. The sprout leaveshave gold-yellow, thread-like tips and protrude between the tubular flowers. The broadened base of these spreader leaves is translucent, provided with a yellow line. During flowering, the plant can sag under its weight. This problem can be solved by grouping the feet together so that the leaves hang together. The mostly eight ray

floret This glossary of botanical terms is a list of definitions of terms and concepts relevant to botany and plants in general. Terms of plant morphology are included here as well as at the more specific Glossary of plant morphology and Glossary ...

s are pink to violet or white colored, at the base may show noticeable stains caused by

anthocyanin Anthocyanins (), also called anthocyans, are water-soluble vacuolar pigments that, depending on their pH, may appear red, purple, blue, or black. In 1835, the German pharmacist Ludwig Clamor Marquart gave the name Anthokyan to a chemical co ...

. The tongues are reversely ovate shaped, have a length of usually () and a width of usually (). The tips are almost dull and have three broad, wavy teeth. Below that, they are greatly rejuvenated. In the center of the flower baskets is a large number of tubular flowers (also called disc florets), whose overgrown petals are yellow, turn white in the lower part and reach a length of . The anthers are brownish-black and about long, at the tips are short-triangular, translucent attachments with a length of . The branches of the stylus are short and rather dull, with a length of .

Range

Garden Cosmos is native to Mexico, Guatemala and Costa Rica. Since it is used as an ornamental plant in many countries and prone to sedimentation, it is an invasive plant in many areas of the world. It has naturalized in scattered locations across North America,

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the souther ...

, the West Indies,

Italy Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical ...

, Australia, and

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an ...

, where it is a garden escape (

introduced species An introduced species, alien species, exotic species, adventive species, immigrant species, foreign species, non-indigenous species, or non-native species is a species living outside its native distributional range, but which has arrived the ...

) and in some habitats becoming a

weed A weed is a plant considered undesirable in a particular situation, "a plant in the wrong place", or a plant growing where it is not wanted.Harlan, J. R., & deWet, J. M. (1965). Some thoughts about weeds. ''Economic botany'', ''19''(1), 16-24. ...

.Biota of North America Program 2014 county distribution map
/ref>

Cultivars

Cultivar A cultivar is a type of cultivated plant that people have selected for desired traits and when propagated retain those traits. Methods used to propagate cultivars include: division, root and stem cuttings, offsets, grafting, tissue culture ...

s of ''Cosmos bipinnatus'' in cultivation today include: *Apollo Series **'Apollo Carmine' ** 'Apollo Pink' **'Apollo White' *'Daydream' features a pink inner ring on a white background *Double Click Series features semidouble to fully double flowers that resemble Japanese anemones (''

Anemone japonica ''Eriocapitella hupehensis'', a species of flowering plant in the buttercup family Ranunculaceae, is native to Asia. The specific epithet ''hupehensis'', which means "from Hupeh (Hupei, Hubei) province, China", refers to a region where the specie ...

'') **'Double Click Cranberries' **'Double Click Rose Bonbon' **'Double Click Snow Puff' **'Double Click Vari Extra' *'Rubenza' * 'Sensation', also known as 'Early Sensation', is a widely available mix of tall varieties ** 'Sensation Pinkie' *Sonata series *'Velouette' * 'Versailles', developed for the cut flower trade, are shorter than the species, with heights remaining below three feet **'Versailles Dark Rose' **'Vesailles Tetra' (those marked have gained the

Royal Horticultural Society The Royal Horticultural Society (RHS), founded in 1804 as the Horticultural Society of London, is the UK's leading gardening charity. The RHS promotes horticulture through its five gardens at Wisley (Surrey), Hyde Hall (Essex), Harlow Carr (No ...

Award of Garden Merit The Award of Garden Merit (AGM) is a long-established annual award for plants by the British Royal Horticultural Society (RHS). It is based on assessment of the plants' performance under UK growing conditions. History The Award of Garden Merit ...

Cultivation

Growth characteristics of this plant include: *

Germination Germination is the process by which an organism grows from a seed or spore. The term is applied to the sprouting of a seedling from a seed of an angiosperm or gymnosperm, the growth of a sporeling from a spore, such as the spores of fungi, ...

takes between 7 and 10 days at the optimal temperature of ; flowering begins between 60 and 90 days after germination * It prefers a soil pH between 6.0 and 8.5, reflecting its native habitat in the alkaline regions of

Central America Central America ( es, América Central or ) is a subregion of the Americas. Its boundaries are defined as bordering the United States to the north, Colombia to the south, the Caribbean Sea to the east, and the Pacific Ocean to the west. ...

* Flowering is best in full sun, although partial shade is tolerated Excessive rain can cause cultivation problems, due to the delicate nature of the stems. Heavy rain can cause breakage. ''Cosmos bipinnatus'' can tolerate heat as long as adequate moisture is provided, however, it does not handle droughts, strong winds or cold temperatures well. Snails, slugs and

aphids Aphids are small sap-sucking insects and members of the superfamily Aphidoidea. Common names include greenfly and blackfly, although individuals within a species can vary widely in color. The group includes the fluffy white woolly aphids. A t ...

have a taste for ''Cosmos bipinnatus''. Successfully cultivated plants can mature x .

Pollinators

The flowers of ''Cosmos bipinnatus'' attract birds and butterflies, including the

monarch butterfly The monarch butterfly or simply monarch (''Danaus plexippus'') is a milkweed butterfly ( subfamily Danainae) in the family Nymphalidae. Other common names, depending on region, include milkweed, common tiger, wanderer, and black-veined brown. ...

. It can be part of

butterfly gardening Butterfly gardening is a way to create, improve, and maintain habitat for lepidopterans including butterflies, skippers, and moths. Butterflies have four distinct life stages—egg, larva, chrysalis, and adult. In order to support and sustain ...

and pollinator/honey-bee

habitat garden A wildlife garden (or wild garden) is an environment created by a gardener that serves as a sustainable haven for surrounding wildlife. Wildlife gardens contain a variety of habitats that cater to native and local plants, birds, amphibians ...

Gallery

file:Cosmos bipinnatus7.jpg, Typical range of colours in a dense stand file:Cosmos bipinnatus 'Double Click' Leaves 1600px.jpg file:Cosmos bipinnatus flower bud.jpg file:Cosmos_bipinnatus_(5).jpg file:Cosmos bipinnatus 09 ies.jpg, alt=Detail of florets file:Cosmos bipinnatus 10 ies.jpg, Lateral aspect, alt=Detail, lateral aspect file:Seeds of Cosmos bipinnatus 2012.08.13 15-52-05.jpg, Seeds file:Schmuckkörbchen mit Biene.jpg file:Cosmos bipinnatus (Asteraceae) with an Andrena sp. bee.jpg , ''

Andrena ''Andrena'' is a genus of bees in the family Andrenidae. With over 1,500 species, it is one of the largest genera of animals. It is a strongly monophyletic group that is difficult to split into more manageable divisions; currently, ''Andrena'' i ...

'' sp. pollinating File:Pink cosmos 03481.jpg File:R10_kamera_049be.jpg File:大波斯菊 20190926161741 09.jpg

References

External links

Cosmos history and cultivation, Texas A&M University

- Press and video * Jepson Manual Treatment
Jepson Manual, University of California, Cosmos bipinnatus

United States Department of Agriculture Plants Profile

''Cosmos bipinnatus''
- Calphotos Photo gallery, University of California {{Taxonbar, from=Q575748 bipinnatus Flora of Mexico Garden plants of North America Butterfly food plants Annual plants Plants described in 1791 Taxa named by Antonio José Cavanilles