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fertilizer question

keegan99usa

LawnSite Member
Does this make sense? A guy at the golf course told me that in the spring use a fertilizer with the middle number the highest. Then in late spring or summer use one with the first number highest. He said that the second number is suppose to help the roots most. What would be a good ferttilizer with a high second number count. That's phosphorus right?
Keegan
 

GripB

LawnSite Member
Go to Lesco.com and type in your zip code to see if there is a Lesco near you. You can open a "home owner" cash/credit account there. You can get good fertilizer along with good advice. Just a thought.
p.s. - Scotts is OK, but super high in "N".
 

GripB

LawnSite Member
Here in PA they do, but you won't get discounts unless you buy big quantities.
 

Critical Care

LawnSite Bronze Member
Location
Central Oregon
You know, how high is high is all relative. What Harmon said about the 18-24-12 fertilizer is what I'd state as being high in phosphorus, as well as okay in nitrogen and potassium. There are super-phosphates that may look like 0-45-0. Unless if you are targeting a new lawn, new sod or seed, then I’m not sure why you would go with a high phosphorus fertilizer. The ionization of phosphorus causes it to leach from the soil very slowly, perhaps only a few centimeters per year, and so I’m trying to figure out why it would be of importance on an established lawn. Hmm… someone tell me.

If you want a green lawn in the spring then you need to give it nitrogen. Nitrogen is not found naturally in the soil and needs to be replenished because it, being of the same polarity as the soil, will not adhere to the soil particles but instead will leach rapidly. My personal opinion… and guys tell me if you don’t agree… is to go right now with a cool season fertilizer relatively high in nitrogen, but contains both quick and slow release types of nitrogen. It would probably also contain a percentage of sulfur and iron
 

lars

LawnSite Member
Location
Pittsburgh
Phosphorus is used to promote root growth. However, high amounts of phosporus are usually not needed. Current research shows that for maintenance purposes only about 2 lb phosphate / 1000 ft is needed per year. Now there are exceptions to this. Keegan, your freind's greens may be poa annua (annual bluegrass), which love high amounts of P. Alot of things can vary. I would not worry about P and stick to 2-2.5 lb a year. Another thing you should do is apply fert with K rates similar to N, as K is important is keeping a healthy plant.

Critical Care, how dare you say that nitrogen is not found in the soil naturally. If a soil contains any organic matter, it contains nitrogen. Bacteria break down OM and make nitrogen. However, it is usually consumed faster than it is made. OM is a big factor in making a "good" soil and is often the reason as to why a soil is so producive.
 

Critical Care

LawnSite Bronze Member
Location
Central Oregon
Just to explain this nitrogen thing a bit further, if you took away the nitrogen out of the atmosphere then we would loose it in the soil. You will find in four different forms, and only two can be used directly by plants - ammonium and nitrate. Atmospheric N makes up about 80% of the soil atmosphere, but is the sorce of N for N-fixing plants. Through nitrogen fixation and Rhizobia bacteria, certain plants can take nitrogen gas and convert it over to available nitrogen within the plant. This is why so many people plant legumes, which are good N converters.

Organic N is not available to plants, but is mineralized to ammonium by soil microorganisms.

And, soil microbes - especially during the wet season - convert nitrate to nitrogen gases, which diffuse back into the atmosphere. It's a cycle type of thing, but nitrogen is a naturally found gas in the atmosphere.
 

lars

LawnSite Member
Location
Pittsburgh
Critical Care, kudos to your great knowledge of the turfgrass edaphic enviroment. It seems that your latest statement is much better than the first. You made it seem that there is no nitrogen in the soil and the only way it can get into the soil was through fertilizer. It seems that both of us know that plant-available nitrogen is in any good soil due to microorganisms. The point is, you usually need more.

However, I would like to address what you said about leaching. In MOST soils. leaching occurs when you use a nitrate-based fertilzer. Most soils have a negative charge. Negative soils + negatively charged nitrogen = leaching. If you use ammonium (a positive charge), it will adhere to soil particles.
 
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