Ask the Expert: Bloom and Nitrogen

Many farm customers seek out Bloom specifically as a sustainable, affordable, organic form of nitrogen. Nitrogen is one of the three primary plant nutrients (along with phosphorus and potassium), which simply means that they are required by plants in greater quantities than other nutrients. Indeed, nitrogen is probably the most important for plant growth. Farmers, turf managers, landscapers and gardeners alike understand that when plant foliage starts turning yellow and their growth stunted, additional nitrogen is probably required.

Nitrogen is so critical for plant development because it’s a primary component of chlorophyll, amino acids, and nucleic acids, molecules essential for photosynthesis, protein synthesis, and genetic material respectively. Nitrogen also plays a vital role in plant structure, metabolism, and overall growth.

Nitrogen can be supplied to plants in various ways and in many forms; rainwater even contains small amounts of nitrogen, in the form of nitrates and ammonium. While a few plant species can fix nitrogen from the atmosphere, most absorb it from the soil (more precisely from the soil water). Nitrogen is often referred to as being in a “quick release” or “slow release” form. Most chemical, otherwise known as inorganic, forms of nitrogen are quickly releasing (in ammonium or nitrate forms) and therefore more prone to loss in a gaseous form (ammonia volatilization) or through leaching in water (nitrate form).

Organic or natural forms of nitrogen are primarily in a slowly releasing form; soil microbes actually have to convert it into plant available forms over time for plants to use it.  Nitrogen in this form has a much smaller chance of migration and loss, making it much less likely to cause environmental harm. Further, slowly releasing forms of nitrogen possess a much lower “burn potential” (salt burn), so they are less likely to harm plants if overapplied.  This is the form of nitrogen provided by Bloom products. Specifically, the nitrogen in Bloom products is 80 to 90+% in slowly releasing form. It is a little bit more complicated to determine the precise nitrogen content of products like Bloom (and compost) because they contain a much higher amounts of moisture than do dry, granulated fertilizer products.

Products like Bloom are typically used for their ability to improve soil quality, by acting as a source of organic matter. The nutrients contained in Bloom are often considered to be a bonus to its use. That stated, farmers often use biosolids-based products as a primary source of nitrogen and phosphorus. Remember that different plant species require different amounts of nitrogen on an annual basis. For example, turf species and many small fruits and vegetable plants require much more nitrogen than do ornamental plants, trees and shrubs. Therefore, it is much easier to be able to satisfy an ornamental flower bed’s annual nitrogen requirement by using Bloom (at soil conditioning application rates), than it is to do the same with athletic field turf.

It is important to remember that the nitrogen in Bloom must be made available to plants through natural microbial activity; known as mineralization.  This is the microbial process of decomposing organic matter, which also converts the nitrogen attached to the organic matter into plant available forms (nitrate and ammonia). So, only approximately 25% of the nitrogen in Bloom may be available the first year after application, less the second year and even less the third year. While some of the remaining nitrogen may be lost, most of it is immobilized and used by other creatures (microbes) living in the soil. When these creatures die, their nitrogen is then mineralized and made available to plants. Note that chemically based, slowly releasing nitrogen products usually release nitrogen over a one-year period.

To estimate the amount of nitrogen available to your plants and/or crop species, use the nitrogen figures on the table below.

Approximate* and Estimated Amounts of Total Nitrogen Content: