Cleome viscosa L.

Northern Cameroon: Cleome viscosa is present throughout the rainy season, but in cultivated fields, it is particularly abundant at the start of the crop cycle. Germination begins in May, either after an early plowing, or before plowing when it is done late. Flowering and fruiting occur very quickly. The first flowers bloom two weeks after emergence and the first capsules are formed a week later. The first seeds can be released in late June. The plant continues to grow throughout flowering. The speed of the development cycle allows this plant to ensure its reproduction as from the beginning of the wet season, provided that cultivation of weed control operations are sufficiently spaced in time. After each tillage operation (weeding, ridging), new saplings appear. Whatever the time of germination, all individuals dries up at the end of the rainy season (September-October). Individuals germinated later have a development and production much less important than those seeds germinated at the start of the cycle. On temporarily flooded fields, the development cycle can take place early in the dry season when the soil is drier.
Mayotte: Cleome viscosa flowers and fruits all the year round.
Reunion: In sugarcane crop at low altitude, tillage at planting seems to cause massive emergence of Cleome viscosa at the beginning of the crop cycle. On the other hand, in mulched sugarcane regrowth, the emergence of Cleome viscosa is much lower; the mulch seems to prevent emergence.

Cleome viscosa behaves more like a non-nitrophic species.

Northern Cameroon: Cleome viscosa is a ruderal species common along the roads and nearby villages. It is abundant in young fallows. It is also a weed of annual crops. It grows mainly in Sudano-Sahelian region where annual rainfall is between 900 and 1200 mm.
Comoros: ruderal species, observed in all regions of low altitude of the island of Grande Comore.
Madagascar: ruderal and weed species of rainfed crops in low and medium altitude area, with a marked dry season (Middle-West, West, Northwest and Southwest) on the edges of roads in fallows and rainfed crops.
Mauritius: Common weed in sugar cane fields and uncultivated land, especially at low altitude.
Mayotte: C. viscosa is widely naturalized in all the anthropized environments, in particular in urban zone, in the waste lands, in the cultures and along the roads. It grows mainly in the central zone of the island.
Reunion: It is a ruderal species uncommon in Reunion.
Seychelles: Species of clearings and cultivated areas. It is rarely abundant.
West Indies: Cleome viscosa is an exotic species. It is present in sub-humid regions on clay soil. It rapidly colonises agricultural plots after each tillage operation (ploughing, weeding, etc.). 

Global harmfulness

Occasionally a noxious weed.

Local harmfulness

Northern Cameroon: C. viscosa is a species characteristic of Garoua, where it is present in over 40% of plots and can be very abundant. However, in the Sudanese region of northern Cameroon, its frequency is only 4% and10% in Sudano-Sahelian zone. This species is typically a potential regional weed. It grows on sandy or stony soil, including ferruginous degraded soil. It also grows on periodically flooded alluvial.
Comoros: first major weed of crops such as cassava plantations or corn.
Madagascar: slightly harmful species.
Mauritius: Weed common in areas of low rainfall where it has a relatively low harmfulness.
Mayotte : Cleome viscosa is a rare weed, observed only in 1% of cultivated plots. It is mainly present in vegetable crops, especially in the center of the island.
Reunion: C. viscosa is a weed of annual crops and appears mainly at the start of the crop cycle. It occurs in one floristic survey in sugarcane cultivation in the south of the island.
Spain: it is a troublesome weed on irrigated crops in arid areas.
Seychelles: A weed of low harmfulness.
USA: it is considered a noxious weed.
West Indies: Cleome viscosa is a common weed in vegetable and food crops and less so in established banana and sugarcane crops. It locally colonises orchards in dry areas where it sometimes forms a monospecific plant cover.

Control

Due to its rapid growth it should be controlled in some annual crops. Besides the normal hoeing, soil-applied herbicides (monolinuron, trifluralin, chlorbromuron, atrazine, prometryne, terbutryne, metribuzin, diuron, oxadiazon) have been successful, but alachlor and fluorodifen are inefficient. Some foliar-applied herbicides (MCPA, 2.4-D and paraquat) are equally effective.

In spite of its well-branched taproot system, Cleome viscosa is easy to pull out (e.g. much more easily than Sida sp.).

Management recommandations for annual broad-leaved weeds in rice fields: http://portal.wiktrop.org/document/show/20

Herbarium pictures ReCOLNAT: https://explore.recolnat.org/search/botanique/simplequery=Cleome%2520viscosa