Vegetable crops in Guyana

Guyanese climate

In Guyana, the climate subject to the movements of the ZIC (intertropical convergence zone), is of the equatorial type. It is characterized by a significant rainfall regime, with up to 4.5 m of water per year in certain areas, particularly in Cacao. On the other hand, in the Saint-Laurent, Mana and Javouhey sector (important areas of market gardening), rainfall varies between 2000 mm and 2500 mm/year on average.
Rainfall is usually heavy and short-lived. It is not uncommon to record daily waterfalls of more than 100 mm, sometimes causing flooding in the fields located at the edge of the creek.
The humidity is also very high, which is conducive to the development of certain fungal diseases. Relative humidity varies from a minimum of 50% in the dry season to 98% in the wet season.
Average temperatures are around 26.5°C. They are fairly stable all year round and the day-night gradients are low. High temperatures greatly influence the cycle times of insect pests, which will multiply very quickly in humid tropical conditions.

The ZIC oscillates from north to south, watering Guyana twice a year. Thus, from August to mid-November when the ZIC is located far to the north, Guyana is in the middle of the dry season. From mid-November to mid-February, the ZIC descends towards the south, crosses Guyana and causes the short wet season followed by a month-long lull, called the “little summer of March”. The great wet season follows from May to mid-June (unstable in July), when the ZIC reaches the equator, rises and crosses the region again.

Jean-Jacues de GRANVILLE & Marc GAYOT. 2014. Guide to the Palms of Guyana. ONF: French Guiana (FR), 272p.

Brief description of soils

Guyana is part of what is known as the "Guiana Shield", characterized by a cratonic crust, the upper part of which is composed of granitic rocks and the lower part of continental (granulitic) crust. The Guiana Shield has undergone, for millions of years, the alternation of a hot and humid climate which has gradually altered its surface giving way to deep aged and impoverished soils. There are also rocky outcrops, called cuirasses, hardened soils resulting from the crystallization of iron and aluminum. These granitic and ferralitic reliefs make up part of the Guyanese landscape.
We find part of this hilly landscape in the agricultural regions of the east (From Cacao to Saint-Georges), suitable for arboriculture and citrus growing.
The coastal plain of Guyana is more marked by the presence of savannas and swamp forests. This area is characterized by hydromorphic alluvial soils, especially along the watercourses. To the northwest, between the communes of Iracoubo and Saint-Laurent du Maroni, the soils are covered with very leached, impoverished sandy sediments, commonly known as "white sands".
In addition, there are red soils rich in iron oxides (acid and compact) as well as more drained, clayey-sandy soils. This brief description of the soils highlights several constraints to the production of vegetables on the territory: in the white sands of Guyana, organic matter is quickly leached whatever the season. Elsewhere, acidity and hydromorphy are elements that block the proper biological functioning of soils and therefore the nutrition of plants.

Guyanese soils, roughly described, are rather hydromorphic, acidic, clayey and ferralitic. These characteristics are rather constraining for the production of vegetables. Organic matter levels are also very low. The soil context of Guyana often leads farmers to liming their soil in order to raise the pH. Market gardening is generally practiced in the lowlands while fruit growing is present on the hillsides.

The general agricultural context  

Market gardening farms are small: the areas per farm rarely exceed 5 ha. There are nearly 6,000 farm managers in French Guiana.
The useful agricultural area is still increasing in French Guiana: it reached nearly 31,000 ha in 2014. The crop area dedicated to vegetable production is around 5% of the total UAA. If we include tubers, we reach 26% of the UAA.
Within vegetable crops, the most produced species in terms of area according to the last agricultural census are: cabbages (370 ha), cucumbers (175 ha), watermelons (240 ha), tomatoes (150 ha including 35 ha in an above-ground greenhouse), sweet corn (145 ha). Tubers (cassava in the lead with 5970 ha, yams, dachine, etc.) occupy 6930 ha.

Vegetables grown in Guyana

In Guyana, as in other overseas departments, there is a wide variety of cultivated vegetables.

• Fruit vegetables: Solanaceae (tomatoes, eggplants, peppers, peppers, antrua, etc.); cucurbits, which are particularly numerous in Guyana (cucumber, zucchini, watermelon, melon, sorossi, giraumon, etc.); Malvaceae (Calou…)
• Beans: Mainly vignas called kilometer beans and pigeon peas. “Phaseolus” common beans are quite rarely grown in Guyana.
• Aromatic herbs: Quite numerous in Guyana: fever struck off, parsley, celery, coriander leaf, spring onion, mint, etc.
• Leaf vegetables: Headed and Chinese cabbage, brèdes mafane, amaranth, local spinach (baselles), lettuce, water bindweed, arugula, dachine leaves.
• Tubers and other root vegetables: Dachine, yams, cassava, sweet potato are mainly grown for their tubers in Guyana. For some time now, we have been observing the development of the flying potato on a few farms, for the time being confidential. Turnips and, to a lesser extent, radishes are also produced.
• Ginger and turmeric are aromatic rhizomes.

Note that the classification reveals some weaknesses since dasheen or cassava leaves are sometimes eaten cooked as leafy vegetables.

Market gardening systems

For vegetable crops, a few major types of production systems can be distinguished in Guyana:

• The abattis : they constitute fairly large cultivated areas resulting from the clearing of forests. On these plots, irrigation is rainfed and the plants are directly subject to the vagaries of the climate. The following are generally cultivated: bananas, cassava, peppers, papayas, pumpkins, etc. This is informal agriculture geared towards self-consumption and the sale of surpluses. This small family farming is not very dependent on inputs. Little income-generating, some of this operator develop specialized plots by cultivating watermelon, bananas, yams, sweet potatoes.
• Small-scale intensive agriculture which consists of cultivating on small plots with very short rotations. These plots are generally separated by deep ditches which provide drainage during intense rainy periods: this is ridge cultivation. Irrigation is in most cases provided by a sprinkler system. However, we sometimes observe small artisanal greenhouses with the use of drip. Irrigation is carried out with surface water from flooded lowlands in the West while water is taken from streams in Cacao and Regina. . This is the type of agriculture that consumes the most inputs: pesticides and fertilizers. Drip irrigation is very rare.
• Above-ground greenhouses : a system under development, there are a few near Stoupan, Montsinéry, Kourou, etc. The main crops are: tomatoes, lettuces, melons. In western French Guiana, agriculture under shelter encounters difficulties in developing because of the lack of means: access to pressurized water, electricity (lack of automation)...

The sale of market garden produce

All of the local vegetable production is directly consumed in Guyana. The markets of Cayenne, Saint-Laurent, Javouhey… are often taken by storm by customers. Despite a certain lack of structuring of the vegetable sector, local vegetables can be found in supermarkets. A cooperative is being structured in Javouhey. Seasonal variations in the climate have an impact on the volumes produced: there is therefore a certain price volatility depending on the climatic seasons. For example, the excess rain during the 2015 wet season led to an increase in the price of lettuce on the Cayenne market to €11/kg.

Source of the figures: AGRESTE
For the climate: Meteo-France sources