| Ageratum houstonianum | |
|---|---|
 | |
Scientific classification  | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Clade: | Asterids |
| Order: | Asterales |
| Family: | Asteraceae |
| Genus: | Ageratum |
| Species: | A. houstonianum |
| Binomial name | |
| Ageratum houstonianum | |
| Synonyms [1] | |
Synonymy
| |
Ageratum houstonianum, commonly known as flossflower, bluemink, blueweed, pussy foot or Mexican paintbrush, is a cool-season annual plant [2] [3] often grown as bedding in gardens. [4]
This herbaceous annual or dwarf shrub grows to 0.3–1 m (1 ft 0 in – 3 ft 3 in) high, with ovate to triangular leaves 2–7 cm (0.79–2.76 in) long, and blue flowerheads (sometimes white, pink, or purple). The flower heads are borne in dense corymbs. The ray flowers are threadlike and fluff-haired, leading to the common name. The narrow lanceolate bracts are pointed, denticulate only at the top and glandular hairy. The flowering period is from May to November in the northern hemisphere. [5] The plant attracts butterflies. [6]
The plant is native to Central America in Guatemala and Belize, and adjacent parts of Mexico, but has become an invasive weed in other areas. It was also naturalized in large parts of the tropics and in the southern United States. Its habitat is pastures, moist forest clearings and bushes up to altitudes of 1,000 metres (3,300 ft).
Today, it is widely used as an ornamental plant for summer borders and balcony boxes, high varieties also as cut flowers. The species is cultivated once a year, having numerous varieties whose crowns may be dark blue, purple, pink and white. Preferring cool soils and exposure in full sun, high varieties reach stature heights up to 60 centimetres (24 in). [7] [8]
Ageratum has evolved a unique method of protecting itself from insects: it produces a methoprene-like compound which interferes with the normal function of the corpus allatum, the organ responsible for secreting juvenile hormone during insect growth and development. This chemical triggers the next molting cycle to prematurely develop adult structures, and can render most insects sterile if ingested in large enough quantities. [9]
Ageratum houstonianum is toxic to grazing animals, causing liver lesions. [10] [11] It contains pyrrolizidine alkaloids. [12]
Ageratum houstonianum is prone to becoming a rampant environmental weed when grown outside of its natural range. It has become an invasive weed in the United States, Australia, Europe, Africa, China, Japan, New Zealand, and the Philippines. [13]
The cultivars 'Blue Danube' [15] and 'Blue Horizon' [16] have gained the Royal Horticultural Society's Award of Garden Merit. [17]
Trillium erectum, the red trillium, also known as wake robin, purple trillium, bethroot, or stinking benjamin, is a species of flowering plant in the family Melanthiaceae. The plant takes its common name "wake robin" by analogy with the European robin, which has a red breast heralding spring. Likewise Trillium erectum is a spring ephemeral plant whose life-cycle is synchronized with that of the forests in which it lives. It is native to the eastern United States and eastern Canada from northern Georgia to Quebec and New Brunswick.
Lupinus polyphyllus, the large-leaved lupine, big-leaved lupine, many-leaved lupine, blue-pod lupine, or, primarily in cultivation, garden lupin, is a species of lupine (lupin) native to western North America from southern Alaska and British Columbia and western Wyoming, and south to Utah and California. It commonly grows along streams and creeks, preferring moist habitats.
Fritillaria meleagris is a Eurasian species of flowering plant in the lily family Liliaceae. Its common names include snake's head fritillary, snake's head, chess flower, frog-cup, guinea-hen flower, guinea flower, leper lily, Lazarus bell, chequered lily, chequered daffodil, drooping tulip or, in the British Isles, simply fritillary. The plant is a bulbous perennial native to the flood river plains of Europe where it grows in abundance.
Anemonoides nemorosa, the wood anemone, is an early-spring flowering plant in the buttercup family Ranunculaceae, native to Europe. Other common names include windflower, European thimbleweed, and smell fox, an allusion to the musky smell of the leaves. It is a perennial herbaceous plant growing 5–15 cm (2–6 in) tall.
Ageratum is a genus of 40 to 60 tropical and warm temperate flowering annuals and perennials from the family Asteraceae, tribe Eupatorieae. Most species are native to Central America and Mexico but four are native to the United States.
Dictamnus albus is a species of flowering plant in the family Rutaceae. It is also known as burning bush, dittany, gas plant or fraxinella. This herbaceous perennial has several geographical variants. It is native to warm, open woodland habitats in southern Europe, north Africa and much of Asia.
Echium vulgare, known as viper's bugloss and blueweed, is a species of flowering plant in the borage family Boraginaceae. It is native to most of Europe and western and central Asia and it occurs as an introduced species in north-eastern North America, south-western South America and the South and North Island of New Zealand. The plant root was used in ancient times as a treatment for snake or viper bites. If eaten, the plant is toxic to horses and cattle through the accumulation of pyrrolizidine alkaloids in the liver.
Celosia argentea, commonly known as the plumed cockscomb or silver cock's comb, is a herbaceous plant of tropical origin in the Amaranthaceae family from India and Nepal. The plant is known for its very bright colors. In India and China it is known as a troublesome weed.
Heliotropium arborescens, the garden heliotrope or just heliotrope, is a species of flowering plant in the borage family Boraginaceae, native to Bolivia, Colombia, and Peru. Growing to 1.2 m (3.9 ft) tall and broad, it is a bushy, evergreen, short-lived shrub with dense clusters of bright purple flowers, notable for their intense, rather vanilla-like fragrance. Common names also include cherry pie and common heliotrope. Note that the common name "garden heliotrope" may also refer to valerian, which is not closely related.
Geranium sanguineum, common names bloody crane's-bill or bloody geranium, is a species of hardy flowering herbaceous perennial plant in the cranesbill family Geraniaceae. It is also the county flower of Northumberland.
Viola sororia, known commonly as the common blue violet, is a short-stemmed herbaceous perennial plant native to eastern North America. It is known by a number of common names, including common meadow violet, purple violet, woolly blue violet, hooded violet, and wood violet.
Maurandya barclayana, commonly called angels trumpet or Mexican viper, is an ornamental plant in the family Plantaginaceae native to Mexico.
Eutrochium purpureum, commonly known as purple Joe-Pye weed or sweetscented joe pye weed, is an herbaceous perennial plant in the family Asteraceae. It is native to eastern and central North America, from Ontario east to New Hampshire and south as far as Florida, Louisiana, and Oklahoma.
Farfugium japonicum is a species of flowering plant in the family Asteraceae, also known as leopard plant, green leopard plant or tractor seat plant. It is native to streams and seashores of Japan, where it is called tsuwabuki (石蕗).
Symphyotrichum lateriflorum is a species of flowering plant in the aster family (Asteraceae). Commonly known as calico aster, starved aster, and white woodland aster, it is native to eastern and central North America. It is a perennial and herbaceous plant that may reach heights up to 120 centimeters and widths up to 30 centimeters.
Eutrochium maculatum, the spotted joe-pyeweed, is a North American species of flowering plant in the family Asteraceae. It is widespread through much of the United States and Canada. It is the only species of the genus Eutrochium found west of the Great Plains.
Echium pininana, commonly known as the tree echium, pine echium, giant viper's-bugloss, or tower of jewels, is a species of flowering plant in the borage family Boraginaceae. It is endemic to the Canary Islands, where it is restricted to the island of La Palma. Echium pininana is an endangered species, and is listed in Appendix I to, and is therefore protected under, the Convention on the Conservation of European Wildlife and Natural Habitats. The specific epithet pininana is Latin for "small pine", though E. pininana is neither closely related to the pine, nor does it resemble that plant.
Cyclamen persicum, the Persian cyclamen, is a species of flowering herbaceous perennial plant growing from a tuber, native to rocky hillsides, shrubland, and woodland up to 1,200 m (3,900 ft) above sea level, from south-central Turkey to Lebanon-Syria and the Palestine region. It also grows in Algeria and Tunisia and on the Greek islands of Rhodes, Karpathos, and Crete, where it may have been introduced by monks. Cultivars of this species are the commonly seen florist's cyclamen.
Heliopsis helianthoides is a species of flowering plant in the family Asteraceae, known by the common names rough oxeye, smooth oxeye and false sunflower. It is native to eastern and central North America from Saskatchewan east to Newfoundland and south as far as Texas, New Mexico, and Georgia.
Delphinium elatum is a species of flowering plant in the buttercup family Ranunculaceae, known by the common name alpine delphinium or candle larkspur. It is native to temperate Asia and Europe, it is an erect herbaceous perennial growing to 1.8 m (5.9 ft), with deeply divided leaves. It produces spikes of blue or purple flowers in summer.
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