Water as needed. Do not let the soil dry out. Soon after emergence, thin the beans to three plants per container by clipping. Thinning should be done as soon as possible after emergence to reduce the amount of herbicide removed by discarded plants. It is not necessary to thin the oats.
Sunlight is essential for the development of atrazine injury symptoms.
Artificial light has much less intensity than sunlight and, therefore, is not entirely satisfactory. When low atrazine levels are present, atrazine symptoms normally appear in two weeks, providing moisture, temperature and light have been favorable. At about the same time a brown speckling may appear near the soybean leaf edges. Eventually chlorosis may spread through the whole leaf. Plants growing in charcoal treated or uncontaminated soil should be normal.