NITROGEN FERTILIZER TYPES
Nitrogen is the key nutrient in promoting healthy growth and development of plants, including grass in lawns. There are different forms of nitrogen that can be used in lawn care, each with its own advantages and trade-offs.
- Urea: Urea is a common form of nitrogen-rich fertilizer that is widely used in lawncare. It is an easy-to-use form of nitrogen that is quickly absorbed by the grass roots. Urea is also readily available, which makes it a convenient choice for homeowners.
- Nitrate: Nitrate is another form of nitrogen fertilizer that is used in lawncare. It is fast-acting and provides quick results. Effective in cold, wet soils commonly encountered in early-season applications.
- Ammonium: Ammonium is a form of nitrogen fertilizer that takes longer to become available to the lawn. The reason is because soil microbes and bacteria must first break ammonium sulfate down so that it can be absorbed by the plant. In cool soils this microbial process takes longer so you won’t see as rapid a turf response. Ammonium Sulfate fertilizer is also beneficial for Idaho’s alkaline soils, as it can help to lower pH levels.
- Sulfate: While Sulfate is a form of sulfur and not nitrogen, it is found frequently in nitrogen fertilizers such as Ammonium Sulfate and enhances turf color, density, and growth. Ammonium Sulfate benefits Idaho’s alkaline soils since it reduces soil pH. Nitrogen and phosphate also benefit from the addition of sulfur as it improves uptake of those nutrients by the grass. Lawns that lack sulfur exhibit an intense yellow color called chlorosis so it is important to ensure its presence in your lawn.
Quick-release vs. Slow/Controlled-Release Nitrogen
Another key consideration when choosing which fertilizer to apply is how much of the nitrogen is slow-release and how much is quick-release. Treatments are added to various forms of nitrogen to make them release more slowly over time, allowing the turfgrass to use nitrogen more efficiently and reducing environmental loss. Although quick-release will show a more immediate turf response you should apply a high percentage of slow-release nitrogen over the season.
For the healthiest lawn, make sure you provide enough nitrogen throughout the year, but be sure not to overfertilize, especially if you're using a fertilizer with very little slow-release nitrogen. Learn more about how much you should fertilize.
Overall, the advantages of different forms of nitrogen in lawn care will depend on the specific needs of your lawn, the soil type, and the climate. Our programs provide a variety of forms of nitrogen specifically designed to suit Idaho lawns throughout the year.