How to read a fertilizer label

Tuesday, April 5, 2011

Proper fertilization is vital to the health of your lawn. In order to make an informed decision about which Jonathan Green fertilizer to use on your lawn, you need to be able to read and understand what the Guaranteed Analysis label tells you. 

Each Jonathan Green fertilizer bag has a name brand, guaranteed analysis and weight. 

The three main components of a lawn fertilizer are Nitrogen (N), Phosphorous (P) and Potassium (K).  These three ingredients are always listed in this order on any fertilizer bag as required by law.  An example would be the 30-5-5 listed below.  Nitrogen, the first number, promotes top growth, and grass plants need this most during the growing season.  This Nitrogen number is usually the highest on fertilizer bags.   Phosphorous, the second number promotes root growth.  Potassium, the third number is vital for growth and overall plant health and is sometimes referred to as Potash.   Some fertilizers, like Jonathan Green’s Winter Survival, also contain micro-nutrients such as iron and sulfur and more.

There are many brands and fertilizer numbers out in the market that can become confusing so be sure to use Jonathan Green Fertilizers, which will make your choice easy.  Jonathan Green New Seeding Lawn Fertilizer incorporates a higher Phosphorous number to get the roots systems growing.  Jonathan Green Winter Survival fertilizer has a high content of Potash to help the grass plants survive the harsh winter weather. 

The fertilizer analysis represents a percentage of each ingredient so a 30-5-5 analysis of a 15 lb. bag contains:           

 30% x 15 lbs. = 4.5 lbs. of Nitrogen

 5% x 15 lbs. = .75 lbs. of Phosphorous

 5% x 15 lbs. = .75 lbs. of Potash.

If this bag is labeled to cover 5,000 square feet, you divide 4.5 lbs. of Nitrogen by 5 = .90 lbs. of Nitrogen will be applied on the desired area of grass.  In comparison, a 15 lb. bag with a 10-18-20 analysis would only have 10% x 15 lbs. = 1.5 lbs. of Nitrogen and only .30 lbs. of Nitrogen that will be applied on the desired 5,000 square feet of grass area.  

Many times the Nitrogen component will have some “slow-release” characteristics.  These could include Water Insoluble Nitrogen (WIN) or slowly available or “Controlled-Release” Nitrogen.  Products with a high degree of “Controlled-Release” or Water Insoluble Nitrogen (WIN) are desirable.  The Green-Meter Technology Controlled Release Nitrogen in Jonathan Green’s Green-Up Lawn Fertilizer continuously feeds your lawn for up to twelve weeks!  Jonathan Green organic fertilizers have a high level of Water Insoluble Nitrogen (WIN).  These components allow the Nitrogen to be metered out to the plant over a longer period of time for extended greening.  Otherwise, you may have to feed your lawn every month and there is no need to do that with today’s improved Nitrogen technology.   

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