Agricultural Plastics in Sonora for Extreme Heat

Why does Sonora’s extreme heat change the choice of plastic?

Sonora combines very hot summers, winters with cold nights in the valleys, plenty of sun, frequent wind and water that has to be conserved. That mix is different from other regions of the country, and a plastic that works well in a humid, temperate zone can fall short here. Sonoran fields grow vegetables, table grapes, asparagus, citrus and grains, among other crops, and each one asks something different of the film.

The common idea is plasticulture: modifying the crop microenvironment with plastic films. Our catalog defines it as a way to protect plantings from adverse weather, pests and weeds. To see how Sonora compares with other regions, check the guide to agricultural plastics by state.

Which plastic to use for each challenge in Sonora?

How does mulch film work in Sonora’s heat?

Bare soil under summer sun loses moisture quickly and can heat up enough to affect the root. Two-tone agricultural mulch film solves part of the problem. The technical data sheet states that the white side reflects sunlight to reduce soil heating and is recommended in areas of high solar radiation and high temperatures, while the black side blocks light and holds back weeds.

Silver-and-black does something similar, with the advantage that, according to the same data sheet, the reflected light helps reduce insect populations and repel pests and disease vectors. By contrast, black-and-black raises root temperature; it suits temperate or cold climates better than Sonoran heat, except for winter plantings.

Finally, with irrigation getting costlier and more limited, covered soil loses less water to evaporation, and plastic films can save 20% in water consumption; actual results vary with the crop and irrigation.

What is a macro tunnel for in Sonora?

Although Sonora is hot, its valleys have cold winter nights and occasional frosts that damage crops. There are also strong winds and isolated rains that can spoil the fruit. The agricultural macro tunnel covers the row of plants and creates a barrier. The catalog describes it as protection against excessive radiation, wind, heavy rain, frost and hail.

The film can be natural with a UV additive, diffused, anti-drip or with shading. Diffused film spreads light evenly across the whole plant, and shading blocks part of the radiation, which helps when the sun is intense. The catalog lists warranties of 1, 2 and 3 years for natural UV film, depending on the specification. Macro tunnels also make it possible to advance or extend the cycle and harvest outside the traditional season.

When does a water reservoir liner make sense?

In areas with scarce but concentrated rainfall, or with seasonal runoff, it is worth making use of what falls. The water reservoir liner goes in a depression in the ground, adapted to capture rainwater and runoff. The catalog presents it as a way to capture, store and supply water. For the grower, it means having a reserve that complements the well or canal, especially during the part of the year when water is scarce. You can see how it is used in other regions in the article on saving water in La Laguna.

How do you combine the three plastics on one plot?

There is no single recipe, but there is a logical order. First think about water and decide whether it needs to be stored. Then, on the planting bed, choose the mulch film color according to the transplant date and the pests the field has had. Finally, if the crop is sensitive to frost, wind or radiation, add the macro tunnel. If the field has a history of fungus or nematode problems, you can disinfect first with High Barrier film. In another article we compare this with mulch film in Sinaloa, a neighboring state with a similar vegetable cycle.

What mistakes are made with plastic in hot climates?

• Choosing the color out of habit. A black-and-black film in the middle of September heats the root when the goal is to cool it.
• Ignoring the wind. A loose installation or poorly covered edges lift and tear before their time.
• Leaving the macro tunnel without ventilation. In strong sun, a closed structure builds up heat; you have to manage the sides and the schedules.
• Ordering without consulting about the crop. Each film is matched to a crop, a cycle and an irrigation method.

Where can I buy agricultural plastics in Sonora?

At ICUSA we serve Sonora directly from our plant in Culiacán, Sinaloa, and we ship to your region. If you want to talk to someone at the factory, message one of our ICUSA advisors on WhatsApp at 667 791 3171 or through the contact page, with your crop, approximate acreage and planting season, and they will guide you on mulch film, macro tunnel or water reservoir liner.