Effects of Ammonia on Plants

Fields are often treated with ammonia fertilizers to increase plant production.

The single largest use of ammonia is as a fertilizer product. This substance is transformed into both solid and liquid fertilizers and is used throughout the world to promote the growth of large, strong crops. Many chemical compounds based in ammonia are used in the household and commercial fertilizer industries.

Nitrogen

Plants need three primary nutrients to grow. Nitrogen, phosphorus and potassium are the basis of plant nutrition, although other micronutrients are also required. Ammonia-based fertilizers are used to enrich the nitrogen content of the soil. For many crops, nitrogen is the most needed of the three nutrients, which is why ammonia fertilizers are such an important part of the industry.

Yields

Ammonia fertilizer in the right proportions increases the yields of plants in areas where it is applied. This was verified by a study conducted in Alberta over 12 years. The study looked at urea application rather than ammonia, but the study stated that the effects of the two fertilizers are identical due to chemical similarities. The result was that barley crop yields improved by as much as 30 bushels per acre.

Long-Term Nitrogen

Nitrogen is essential for plant growth, but it dissipates quickly in the soil. Ammonia is useful as a fertilizer because it does not disperse quickly the way other sources of nitrogen do. The long-term availability of nitrogen that ammonia provides to a crop ensures that the nitrogen needed for leaf and plant growth is available throughout the growing season to the plants.

Ammonia Injury

Ammonia is a very strong chemical; if you apply it improperly, it can have the opposite of the intended effect on your crops. Apply ammonia-based fertilizers deep so that they are farther away from the seeds in the ground. Young plants can suffer from ammonia injury if seeded to close to the fertilizer. This stunts the plant and sometimes burns off the leaves or roots.

References

• India Agronet: Nitrogenous Fertilizers
• Government of Alberta: Anhydrous Ammonia and Urea Fertilization: Myths and Facts - Frequently Asked Questions
• The University of Illinois; Myths and Truths About Anhydrous Ammonia Fertilizer; April 2011
• University of California; Aqua and Anhydrous Ammonia; O.A. Lorenz

Resources

• University of Minnesota Extension; Using Anhydrous Ammonia Safely on the Farm; John M. Shutske; 2005
• University of Wisconsin Extension; Adding Anhydrous Ammonia to Corn Silage; Ronald T. Schuler
• University of Minnesota: Anhydrous Ammonia