The basic framework of a pre-fabricated house is built inside a factory. The walls and roofing are built in an environment that is ideal for the workers, and building efficiencies are best. However, the house is not completed inside the factory. The pre-built walls and roofing are taken to the building site where the house is completed.

Building a house at a building site where the walls and roofing are already completed takes less building time at the site, and therefore houses go up faster and more efficiently.

Seed priming is like building a pre-fabricated house.

Seed Priming starts the germination process in the lab or plant, like a pre-fabricated house is started in the factory. The basic chemical reactions or framework needed for the seed to germinate occurs in the lab or plant under high moisture and ideal temperature conditions. Seed moistures are set at a level just below what’s needed for actual germination, but just enough to get the process going.

Once the framework for actual germination is built, you can dry the seed down to stable moisture levels and plant the seed at the field site where the rest of the germination process can take place, when the seed comes in contact with soil moisture.

Like the pre-fabricated house, seed germination in the field takes less time, because part of the germination process in already complete.

Primed seed usually emerges from the soil faster, and more uniformly than non primed seed of the same seed lot. These differences are greatest under adverse environmental conditions in the field, such as cold or hot soils. There may be little or no differences between primed and non primed seed if the field conditions are closer to ideal. Some growers use seed priming during the earlier plantings in cold soil, and not later in the season when conditions are warmer. Lettuce growers in the Southwest region of the United States use primed seed in the hottest part of the season, when lettuce may not be able to germinate due to the extreme heat. These growers switch back to non primed seed during the cooler season.

The number one risk when using primed seed is reduced seed shelf life. Depending on the species, seed lot vigor, and the temperature and humidity that the seed is being stored, a primed seed should remain viable for up to a year. If you store primed seed in hot humid conditions, it will lose viability much more quickly. In most all cases however, primed seed has shorter shelf life than the non primed seed of the same seed lot. For this reason, it’s best not to carry primed seed over to the next growing season.

Keith
k.kubik@hmclause.com