Factors studied

Positive effects

Negative effects

- Reduction in weeding time (60% less with paper mulching on yams in the West Indies, 50% less with RCW in market gardening in Guyana).

- Ease of harvesting for certain crops (salads).

- Decreased tillage time before planting and the time required for planting taros ( Colocasia esculenta ) or planting corn ( Zea mays ) and cane peas ( Vigna unguiculata ).

- Increased working time for installation.

- Need for grinding at the end of cultivation for plant mulch.

- Ensure the availability of equipment (example: kraft paper in Guyana).

- Decrease in the cost of labor for manual weeding or treatments.

- Reduction in the cost of herbicide treatments.

- Reduction of water consumption.

- Necessary expenditure for the purchase of manufactured mulch.

- Expense for the manufacture of mulch.

- Acceleration of crop growth in some cases by attenuating thermal variations.

- Longer maintenance of soil moisture which favors the fauna and flora of the soil.

- Protection of the soil structure against the erosive effect of rain.

- Enrichment of the soil with organic matter in the case of plant mulch

- Reduction of the risk of contamination of leaves and fruits in market gardening by certain soil-borne pests (Sclerotinia and Rhizoctonia in lettuce and melon).

- Reduction of leaching.

- Difficulty in evaluating the dynamics of nitrogen, phosphorus and potassium restitution.

- Reduction, for plastic mulch by partial solarization effect, of the emergence rate of young yam shoots.

- In some cases, growth retardation with plant mulch (nitrogen starvation).

- Ignorance of the side effects of species that can be used in plant mulch in French Guiana (allelopathic effect for example).

- Favoring the nesting of rodents by mulching made up of the accumulation of mowed tall grass (possible damage to crops or polyethylene irrigation pipes).

- Better visual aspect due to the cleanliness of the harvested products (less soil).

- Less herbicide residues.

- Technique usable in Organic Agriculture for biodegradable mulches.

- Fight against erosion.

- Preservation of water quality due to less use of herbicides.

- No polluting elements in the kraft paper which can therefore be left in place or buried without affecting the quality of the soil.

- Increase in runoff and accentuation of erosion in the case of impermeable mulching.

- Difficulties in recovering used plastics and recycling them (non-biodegradable film).

- Reduction of fuel consumption if mulching is manual and replaces phytosanitary treatments.