The researchers studied how different planting dates and densities affect the growth of maize plants. They used three maize varieties and tested different planting densities and dates in field experiments. By analyzing dry matter accumulation and grain yield, they developed a model to predict maize growth based on temperature and dry matter accumulation. They found that planting date and density can impact the rate of dry matter accumulation, with the sixth leaf and waxy stage being crucial periods. Overall, early planting and higher densities led to increased dry matter accumulation in maize plants.