Sep 01, 2022

Farmers in Mato Grosso Anxiously Wait for First Summer Rains

Author: Michael Cordonnier/Soybean & Corn Advisor, Inc.

Farmers in Mato Grosso will be allowed to start planting their 2022/23 soybeans when the "Soybean Free" period ends on September 15th. Many areas of the state received their last significant rainfall in April and unfortunately, there is no rain in the forecast for at least the next 6-10 days. The Brazilian National Weather Service is forecasting that the state should receive its first significant rainfall sometime during the second half of September.

Farmers like to receive 1-2 inches of rainfall or more before they start planting their soybeans. That much rainfall is needed to insure germination and adequate stand establishment. If farmers plant too soon after the first light rain, the soybeans may germinate but then run out of moisture and die before further rains occur. There can be several weeks between the first and second rain of the summer rainy season. At the same time, temperatures in central Brazil can be very hot in September and October, so the initial rainfall can evaporate very quickly under the intense sunlight. Temperatures cool down somewhat once the summer rainy season takes hold. The summer rains usually start first in western Mato Grosso and work their way east as the season progresses.

Additionally, the cost of inputs such as fertilizers and chemicals are much higher this year, so farmers will be extra cautious so that they don't have to replant their soybeans.

La Nina is still present in the Pacific Ocean and it could influence the start of spring planting in Brazil for the third year in a row. Generally, La Nina conditions result in hotter and dryer than normal conditions in southern Brazil during the planting season and normal weather conditions in central Brazil.

If the soybean planting is delayed in Brazil due to a slow onset of the summer rains, the soybeans could still have normal yields if the weather is beneficial for the remainder of the growing season. But a delay in the soybean planting could mean a delay in planting the safrinha corn after the soybeans are harvested and that could negatively impact safrinha corn yields.