Fertilizer turns to concrete in spreader

[kubotasam]

A few years back I acquired a well used Baltimatic broadcast type fertilizer spreader. Each time I have used it the bottom of the hopper gets coated with first like a paste from the fertilizer which quickly will turn to a concrete like substance. Today I was trying to spread 300 lbs. About 1/2 way through the opening sealed shut and no more fertilizer would come out no matter what I did with the adjustment levers. I had to stop and get a long 1/2" steel rod and put it down through the fertilizer and hammer on the end till I opened the bottom. I was able to finish my job. I can't imagine what a PITA it would be if I had lots of area to cover. When finished the bottom was covered with what looked like concrete. I got my chipping hammer and could not get it off the bottom. I was slowly able to clean it off by spraying with a water hose. We had a ground driven spreader when I was a kid and I don't remember anything like this happening. Can any body shed some light on what is happening. They can't all do this.

 

[Daren Todd]

Are you mixing two different fertilizers?

I remember reading somewhere, may have been the little booklet that came with my last broadcast spreader. Anyway, it said that mixing an organic based fertilizer with a chemical based fertilizer caused the organic stuff to break down and make a mess, or vice versa. And recommended spreading one type, hosing it out and drying it. Then spread the other fertilizer.

 

[kubotasam]

Are you mixing two different fertilizers?

I remember reading somewhere, may have been the little booklet that came with my last broadcast spreader. Anyway, it said that mixing an organic based fertilizer with a chemical based fertilizer caused the organic stuff to break down and make a mess, or vice versa. And recommended spreading one type, hosing it out and drying it. Then spread the other fertilizer.

Just one type of fertilizer. Bought it today at feed store. Came sealed in plastic bag so very dry.

 

[Ramos]

Sounds like it picked up moisture from somewhere. Keep in mind that your fertilizer is extremely corrosive and will draw moisture from the air and begin to break down. Wash thoroughly after use then protect the metal parts with grease or oil before storing.

 

[Daren Todd]

Just one type of fertilizer. Bought it today at feed store. Came sealed in plastic bag so very dry.

Now that's a who done it I've had some that I had to dump in a wheel barrow and beat the tar out of it before dumping into the spreader to loosen up the chunks. Had chunks of it plug the shoot. But not have it turn while in use.

I tried mixing bug begone in with some triple 13 before. Thinking I was being smart and cut down on trips. The bug begone reacted with the triple 13 and turned to clumps

 

[William1]

I use a walk behind spreader (only 1.5 acres of lawn). I use a Lesco Commercial spreader, all stainless steel and big tires, holds 80 pounds of chemical. I never have had any fertilizer solidifying in the bottom during a spreading. I have seen that only occur with a previously opened bag that absorbed moisture. At most, I have had a two or three pebble size clumps after spreading 300 pounds.

 

[North Idaho Wolfman]

You can mix in some gypsum or lime to make it flow better.

 

[Bulldog]

My spreader has a flat metal piece in the bottom that turns when the pto is on to keep the material from packing. I just spread 40 bags the other day with no issues at all.

 

[kubotasam]

My spreader has a flat metal piece in the bottom that turns when the pto is on to keep the material from packing. I just spread 40 bags the other day with no issues at all.

Mine has a finger like metal piece that rotates down at the bottom of the hopper. It is about 1/4" above the bottom. It is in that 1/4" gap the the paste, then concrete like substance forms. I wonder if the grains of fertilizer get crushed between the finger and the bottom of the hopper then form the paste like substance?

 

[CountryBumkin]

And to add to what everyone else is saying - I see a similar problem with my tow-behind spreader if I use it when the grass is still damp (dew) in the morning. The moisture would get into the bottom of the spreader and clog it (while the fertilizer was dry in the top).
I learned that I could only spread fertilizer in the afternoon once the grass dried out.

 

[kubotasam]

Last year when I put it away I oiled the heck out of it. The bottom of the hopper , the sliding plates and the spinner below. It was very rusted when I got it and did not want any more to happen. Before I used it this time I cleaned it with a rag as best as I could. However I did not use any type of a solvent just a dry rag. I wonder if it could be some reaction between the oil residue and the fertilizer.

 

[Bulldog]

Not saying it can't be but I've sprayed mine down with hyd fluid inside and out for as long as I can remember. Never had any problems.

 

[Ike]

Where did the feed store have these bags stored. If they had been outside they may have sweated inside causing moisture. Take a handful and squeeze it to see if it will pack. If it does do not ill you spreader all the way full. I do one bag at a time when I have had this problem as the weight packs it in the hopper. I have had lime have very hard chunks in it and plug the spinner up so I made a screen using 1/4 hardware cloth and the problem went away. Hope this helps

 

[OldMasterTech]

I would experiment with removing/modifying the agitator if the material is free flowing.

Secondly play with PTO speed, slow as possible without losing desired spread pattern.