Firebush/Hummingbird bush/Scarlet bush/Redhead(Hamelia patens)

Native shrub or small tree of tropical and sub tropical America. Introduced and widely cultivated in home gardens.

අග මුල නැති වැල් [Aga mula neti wel]/Golden Dodder/Field Dodder (Cuscuta campestris)

Introduced and naturalized parasitic leafless vine native to temperate and tropical North America. Common in paddy field margins, roadsides, railway tracks, waste grounds, etc. from sea level to about 1000 m a.s.l. on varies host plants (About 161 plants were observed by a study including rice*) . It is widely distributed in the dry lowlands.  Mikania cordata and Wedelia trilobata appear to be the primary host plants.

අග මුල නැති වැල්/Dodder (Cuscuta chinensis) 

Trimen H., 1895 and Austin, 1980 identified cuscuta spp. found in the low country as Cuscuta chinensis. Trimen in 1895 reported that it is very rare and only found in the suburbs of the Colombo parasitizing on grass, low herbs and shrubs. Austin in 1980 claimed that Cuscuta seeds may have been introduced to the country with imported rice from China. Base on a taxonomical study conducted on Cuscuta species found in the low country in 2004* it was revealed that most probably the above mentioned C. chinensis is an incorrect identification of Cuscuta campestris.

References:

*Jayasinghe C., Wijesundara D.S.A., Tennekoon K.U. & Marambe B. 2004, Cuscuta species in the lowlands of Sri Lanka, their host range and host - parasite association, Tropical Agricultural Research Vol. 16: 223-241 (2004)

Trimen H. 1895, Handbook to the Flora of Ceylon.

Austin D.F. 1980, Convolvulaceae. pp. 305-307, In: Dasanayaka, M.D. & Fosberg F.R.. Revised Hand Book to the Flora of Ceylon, Vol 1.

White Alder (Turnera subulata)

An introduced ornamental herb native to tropical America. Cultivated in gardens. Also escaped and naturalized along roadsides. 

කොටිකන් බැබිල/බැබිල [Bebila/Kotikan bebila]/Paddy's luceme (Sida rhombifolia)

Common indigenous erect herb occurs along river and stream banks, roadsides, waste places, paddy fields, forest clearings, etc. from sea level to to 2000 m elevations.

* Sida alnifolia L. is a synonym of Sida rhombifolia subsp. alnifolia (L.) Ugbor.

Strychnos benthamii

An endemic shrub or small tree, rarely occurs in both wet and dry lowlands. But small leave state is common in the hills.

අසමෝදගම්/Slender Celery/Marsh Parsley (Cyclospermum leptophyllum[Syn: Apium leptophyllum)

Native plant of Eurasia. Introduced and grown as a vegetable. Naturalized in open waste grounds about 1600 m elevations of Haputale. Flowering from March to April and probably also in other months.

Scarlet African Morning Glory (Stictocardia macalusoi)

An introduced ornamental liana native to the southern Somalia. Flowers open at dawn and close near sunset. Cultivated in gardens. Stictocardia beraviensis (Hawaiian Sunset Vine/Hawaiian Bell/Braveheart Vine ) is a closely related species which is extremely hard to tell apart from this.

හීන් මදු/හවරි මදු/ආපසු මදු [Hawari-Madu/Heen-Madu/Apasu Madu] (Xenostegia tridentata [Syn: Merremia tridentata])

Common indigenous vine occurs in disturbed places, roadsides, grasslands, cultivated areas and rocky lands of  both dry and wet lowlands. Commoner in the dry zone. Flowering from April to June.

Southern Duffer (Discophora lepida)

Rather rare butterfly of southwestern wet lowland rain forests with bamboo undergrowth. It flies at dawn and dusk. Larva feeds on Ochlandra stridula [Bamboo/බට] leaves.

China aster (Callistephus chinensis)

An introduced annual herb native to the China and Korea. Cultivated as an ornamental in gardens. Varies cultivars available with flowers of many colors. 

Firewheel/Indian blanket/Indian blanketflower/Indian paintbrush/Sundance (Gaillardia pulchella)

Native plant of North America. Introduced and cultivated in gardens as an ornamental. 

Bluewings/Wishbone flower (Torenia fournieri)

Native herb of Indo China. Introduced and cultivated in gardens. Flowering from March to June and September (Possibly in other months as well). Various cultivars with pink, violet and blue flowers exist.

අඹවිල [Amba wila] (Limnophila repens)

An indigenous decumbent or erect herb widespread in paddy fields, marshlands, etc. from wet lowlands to lower hills. Occasionally also occurs in the wet places of the dry lowlands. Flowering throughout the year.  

Carrot grass/Carrot weed (Parthenium hysterophorus)

Native herb of tropical America. Probably introduced into Sri Lanka in 1988 since it was first observed at the School of Agriculture at Vavuniya which Indian Peace Keeping Force occupied at that time. Now a widely spreading invasive weed of abandoned fields, waste lands, roadsides and cultivated grounds. The plant is toxic and can cause skin and respiratory system problems.

These plant were observed at a roadside location close to the Mathale town (7°27.769'N, 80°37.767'E)

Cape honeysuckle (Tecomaria capensis [Syn: Tecoma capensis])

An introduced ornamental shrub native to the southern Africa. Cultivated in gardens.

පුපුල/හීන් බෝටිය[Pupula/Hin botiya] (Jeffreycia zeylanica [Syn: Vernonia zelylanica])

Common endemic shrub occurs in track sides in patanas, dunes bordering forest scrub at sea level and roadsides up to about 1000 m altitude. Flowering most of the year. 

Blue Lotus (Nymphaea nouchali var. caerulea [Syn: Nymphaea capensis])

An introduced aquatic herb with floating leaves, native to the Africa. Cultivated and also escaped and naturalized in ponds and tanks. Flowering throughout the year. Often confused with the national flower of Sri Lanka - Nymphaea nouchali

Torenia polygonoides [Legazpia polygonoides]

Recent addition to the Flora of Sri Lanka*. Rather rare introduced herb of marshy areas of the southwestern wet zone. Usually grows under shade of shrubs. But also occurs on open places.

* Illustrated field guide to the flowers of Sri Lanka Volume 2, J. & J. de Vlas,2014 

Salvia misella [Salvia riparia]

An introduced perennial herb native to Mexico to Peru and West Indies. Introduced as an ornamental. Escaped and naturalized along roadsides in partial shade in the lower hills and dry lowlands from 200 - 2000 m elevations. Flowering from March to December.

ගැටපිච්ච[Getapichcha]/Arabian jasmin(Jasminum sambac)

Commonly cultivated erect or scandent introduced shrub native to the India. 

Sapphire Fluterer (Rhyothemis triangularis)

Rather rare dragonfly found in marshes, ditches, tanks and slow moving rivers, mainly in the low country wet zone. But there are records also from drier parts of the island. 

අක්කපාන/රට ගෝවා [Akkapana/Rata Gova]/Air plant/Coirama (Kalanchoe pinnata [Syn: Bryophyllum pinnatum])

An introduced herb with fleshy leaves native to the Africa. Naturalized on open rocky places of the low country up to about 1200 m elevations. Probably introduced to Sri Lanka shortly before 1837.

Yellow tabebuia (Handroanthus serratifolius[Tabebuia serratifolia])

Native tree of central and south America. Cultivated as an ornamental tree. Flowering from December to March.

කහ ගෝන කොළ [Kaha Gona Kola] (Adenosma camphorata)

An endemic herb occurs in damp places close to ditches or a watercourse in the wet lowlands below 700 m a.s.l. Flowering from March to December*.

*Flowers observed end of January of  plants growing along the roadside of a fragmented wet lowland forest patch. 

Cuphea micropetala

An introduced woody herb native to the Mexico. Cultivated in gardens. Naturalized plants recorded from a seepage area of a tea estates in Lindula and a disturbed forest near Diyaluma falls (Flora of Ceylon Vol 9).

රත් නෙ‍ටුල්[Rat Netul]/Rosy Flowered Leadwort (Plumbago indica)

An introduced shrub probably native to the Southeast Asia. Cultivated as a medicinal plant since its roots and leaves are used in traditional medicine. Flowering from December to March and rarely from August to December. 

අහු[Ahu]/Great Morinda/Indian Mulberry (Morinda citrifolia)

Common native shrub or small tree occurs mainly along the coast in the wet zone. Also cultivated in inland places. Flowering from September to October. Its roots, leaves and fruits are used in traditional medicine.

Preyer plant (Maranta leuconeura)

An introduced ornamental pot plant native to the Brazil. Cultivated in gardens. 

හෙන්දිරික්කා[Hendirikka]/False Jalapa/Four o' clock, Marvel of Peru(Mirabilis jalapa)

Native herb of Peru. Introduced as an ornamental and cultivated in home gardens. Also escaped and naturalized in waste places. Flowers occurs in white, yellow, purple or pink forms. Flowers open in the late afternoon and close in the morning. Hence the vernacular name Four o' clock.

බූ සේරු[Bu-Seru](Premna tomentosa)

Common native tree or shrub grows in the dry and intermediate low country up to about 1200 m (1500 m?) altitude. Wood use in carving, furniture building and construction industries. Leaves, roots and barks have medicinal values. 

Spathiphyllum cannifolium

Native herb of tropical America. Introduced as an ornamental and cultivated in gardens. Possibly also naturalized in shaded places.  Flowering throughout the year.

අඳු\ගඳකුප්ප[Andu/Gadhakuppa]/Long Coriander/Stink weed (Eryngium foetidum)

An introduced herb native to tropical America. Cultivated and also naturalized along forest edges, shaded or sunny disturbed areas, stream banks, etc. from 550 - 800 m around Peradeniya Royal Botanical Garden. The plant has a very strong unpleasant bug like smell.

මදුරු තලා [Maduru Thala]Sacred Basil/Holy Basil (Ocimum tenuiflorum)

Common native herb occurs along roadsides and open waste places from lowlands to about 530 m elevations. Flowering from December to August. 

පතොක් [Pathok]Velvet opuntia/Nopales opuntia (Opuntia cochenillifera)

An introduced high-growing cactus native to Southern Mexico. Cultivated in gardens as an ornamental and also as a hedge plant.

කටු කරඬු[Katu Karadu]/Yellow Hedge Barleria (Barleria prionitis)

Common indigenous prickly shrub in open waste places and scrub lands in the dry zone. Sometimes also cultivated as a hedge plant. in village dwellings. Flowering from March to August. Whole plant, especially its roots medicinal.

Coral vine/Mexican Creeper (Antigonon leptopus)

An introduced large herb climbing with long tendrils over walls, hedges and other vegetation. Native to the central America. Flowering throughout the year. Cultivated as an ornamental and also escaped and naturalized.

ඒකාවේරිය/නකුල/රත් ඒකාවේරිය[Ekaveriya/Nakula/Rath Ekaveriya]/Indian Snakeroot(Rauvolfia serpentina)

An indigenous sub - shrub  of secondary scrub lands and grassy places of the wet lowlands up to about 700 m elevations. Due to not observing of it during the 'Flora of Ceylon project' Herbert Huber  noted in 1983 that it may have been possibly extinct in the wild due to intense exploitation (Dasanayaka M.D. & Fosberg F.R., 1983, Flora of Ceylon Vol 4). However 2012 Red list categorized it under the Endangered status. It is an important medicinal plant.

Brazilian Red Cloak (Megaskepasma erythrochlamys)

An introduced ornamental shrub native to Venezuela.  Cultivated in gardens.

Mexican poppy (Argemone mexicana)

Native plant of tropical and subtropical North America. Introduced and naturalized in waste and disturbed places, usually near houses. 

බිං දෙළුම්/ඇත් පිටවක්කා[Bin delung/Et pitawakka](Synostemon bacciformis [Syn: Sauropus bacciformis])

An indigenous prostrating herb of sandy saline areas near sea, inland sandy areas near tanks and tidal flat margins.

Dog's tongue (Pseudelephantopus spicatus)

A recent addition to the Flora of Sri Lanka*. An introduced herb native to the Caribbean. First time recorded from altitude 400 m of Peak wilderness. Numerous naturalized plants observed at Meethirigala forest reserve of Gampaha district (Personal observation, 2016/01/29).

* Illustrated field guide to the flowers of Sri Lanka Volume 2 - J. & J de Vlas, 2014

Gaertnera walkeri

An endemic shrub occurs in the hill country forests from 900 to 2000 m a.s.l.

Queen of flowering trees/Pride of Burma (Amherstia nobilis)

Native tree of  Myanmar (Former Burma). Introduced to the Peradeniya botanical garden in 1860 and since then it has been cultivated as an ornamental tree. The Queen of flowering trees is now extinct in the wild.

ඇත් අඩි[Eth adi] (Elephantopus scaber)

Common indigenous herb grows along roadsides, patanas, scrub lands, plantations and as a weed in lawns from lowlands to 2100 m  altitudes in the hill country.Roots and leaves medicinal.

Tail flower/Flamingo flower/Laceleaf (Anthurium andraeanum)

Widely cultivated ornamental pot plant native to Colombia and Ecuador. 

ගඟ වැරැල්ල [Ganga Werella](Phyllanthus myrtifolius)

An endemic shrub occurs along watercourses in forests from 300 to 600 m altitudes. Also planted in home gardens as an ornamental hedge plant.

Cardinals guard (Pachystachys coccinea)

Native shrub of French Guinea, Brazil, and Peru. Introduced and cultivated in gardens. 

හැමනිල්ල[Hemanilla] (Pogostemon auricularius)

An indigenous annual herb occurs among short grass along roadside ditches, paddy field borders, and boggy places in the wet lowlands up to about 1000 m a.s.l. Flowering from October to June. 

කරාබු නැටි[Karabu nati]Clove (Syzygium aromaticum)

An introduced tree native to the Moluccas. Cultivated in intermediate to wet zone home gardens. Buds including the calyx tube are the cloves of commerce, a spice. Also use in traditional medicine. Widely cultivated in the intermediate zone north of Kandy.

Surinam Quassia (Quassia amara)

Native tree of Guiana and tropical South America. Introduced and cultivated in Sri Lanka mainly as an ornamental. It is also used in traditional medicine in some countries and can be used as an insecticide.