Growth Stages of the Sugar Beet

Germination

• Germination is an important growth stage to which farmers must pay particular attention. Germination is temperature and moisture sensitive. For example, sugar beets will not germinate in soil below 37 degrees Fahrenheit or in dry soil. For this reason, most sugar beet farmers plant sugar beet seeds in early to midspring. As sugar beets emerge from the soil, the seedling grows slowly. Only two leaves, the cotyledons, appear at first. It takes between one and two weeks for sugar beets to emerge from the ground.

Canopy Development

• After the sugar beet plant emerges from the ground and opens its cotyledon leaves, it enters its next growth stage: canopy development. Canopy development refers to the blossoming and uncurling of additional leaves on the top of the plant for maximum photosynthesis potential. Sugar beet farmers use a decimal system to determine how each sugar beet plant progresses during this stage. For example, when the cotyledons emerge but no other leaves are visible, farmers refer to this as V 1.0. When the cotyledons and the first and second leaves are visible, the plant has reached V 1.1. V 1.5 occurs when the cotyledons are present and 50 percent of the first and second leaves have unrolled. V 2.5 is when the first two leaves have unrolled completely and a third leaf is visible. This decimal method continues similarly until stage V 9.0 when nine leaves are present and unrolled. The rate at which this growth occurs largely depends upon the environment's temperatures -- the warmer the weather, the faster the growth of the plant.

Root Growth

• While some root growth takes place during the canopy development stage, most of the root grows after the canopy phase slows down. The beet eventually slows down and stops leaf production, and it concentrates on gaining weight beneath the soil's surface to prepare for winter. As the root enlarges, it begins to store sucrose as an energy reserve. Farmers should see the canopy of the plant decline and begin to die as the root grows.

Preharvest

• The preharvest stage usually occurs in early fall of the second year of the sugar beet's life. The root does not fully develop for commercial use until this time. As the light intensity decreases and temperature lowers, photosynthesis in the plant slows. The plant directs nutrients and energy stores to the root as a last ditch effort to prepare for the cold season. It is around this time that farmers prepare to harvest the ripened sugar beets.