Ammonium Sulfate use

Hi! I have a row of 4 fruit trees (apple, cherry, lemon, plum). My young citrus was constantly yellow, I just couldn’t seem to get it enough nitrogen so my arborist suggested Ammonium Nitrate which I’ve been using for a while now (1/2 a pound a few times a year). The lemon tree is now doing great! However my plum and cherry (which are either side of the lemon) have got tons of lush growth but no fruit this year. I’m wondering if maybe the ammonium nitrate is spreading out and causing this excess nitrogen for the other trees. They are about 7.5 to 8 feet apart and they are all fairly young/small trees. When I use the ammonium nitrate I only put it under the drip line of the lemon tree.

So my questions:

  • Do you think the ammonium nitrate would spread out to the neighboring trees?
  • If yes, how can I keep up with the heavy nitrate needs for my lemon without giving the trees next door too much?

Thanks in advance!

The fertilizer can spread some. It depends on lots of things. But It’s more likely that the roots of your plum and cherry trees are reaching the area where you applied fertilizer. The roots will spread past the drip line of the trees.

I thought that ammonium nitrate was banned due to it’s possible use as an explosive. Maybe you aren’t in the US.


Ok thanks…so then how can I feed the high nitrate needs of my lemon without messing up the others? Can I do some kind of foliar spray?

No ammonium nitrate isn’t banned in the US (I am in SoCal) but it is banned in some other countries.

There may be a little bit less to use,as 30 tons of it disappeared between Wyoming and California.

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You can do a foliar spray. But I haven’t done that so can’t give any advice. My thought is that with time the needs of all trees should be about the same. I don’t think citrus needs more than other fruits.

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Please post a photo of the label. I can then provide you with some dosages.

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:astonished: Oh noooooo!

That’s about 3/4 of a rail car’s worth.

If there is a very very bright green swath in the weeds, from Cheyenne to California - they’ll know for sure!

“the leading theory is the disappearance resulted from a leak, and there is no indication the material was stolen.”


I was hoping to get some black market fertilizer for cheap.

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You can get it REAL cheap if you want to follow the train tracks and SCRAPE! :grin: :grin: :grin:

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Sometime early in year, I spotted a pallet of 33-0-0 or maybe it 30-0-0 at the blue colored big box store.
(But, you’d need to be rich to buy a pallet of it!)

Local farm stores carry it.

@Richard thanks! (But isn’t it all the same?!). The tree is about 8 feet tall, 5 feet wide if that helps…

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Nope. Some fertilizer manufacturers produce A/S + micros in a water-soluble powder, etc. Cesco btw is a chemical repackaging company.

If I were to apply this product to my citrus solely as a foliar spray, I’d use 1/4 tsp per gallon once per month. Use enough mixture to so that every leaf is dripping. Do not pour extra into the plant basin.

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This is what I got to use on my blueberries that were showing some chlorosis, probably from the pH creeping up. I had seen @fruitnut talk about using AS for blueberries and got this and my plants look much happier.


Azalea fertilizer is useful for blueberries. Sometimes nitrogen alone is enough to stimulate growth. Sometimes the plant needs a more general purpose fertilizer. I use azalea mix for several acid loving perennials. It is available from most box stores.

Currently at my local Lowes. I havent noticed other fertilizers saying they had Sulfur supplement… but maybe they do.


Awesome thanks Richard! I’ll start doing that instead of the soil application. Hopefully that means my other trees will be OK moving forward…


Its ok to do it less frequently but do not increase the concentration.

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In my area anything and everything winds up beside the road. That includes fertilizer, hay, ag lime, grains etc… Semis haul bone meal for production use. They frequently pull over and sleep beside the road. Sometimes 1000 pounds+ of bone meal is laying there. Stopped once and picked up a few 5 gallon buckets for the tomatos. The rest of the many times i leave it for animals to eat and those who need it. Nitrogen i normally buy in bulk when i need it. Made a deal with a neighbor to purchase it in quantity now. Grass uses lots of it! Thousands of pounds of it does not sound like much to me. We put it on fields at a rate of 150 pounds - 250 pounds per acre for brome. Do the math x 35 acres. The point i’m making is in my area a box car of fertilizers dont seem like much, but it is expensive! Sometimes the clover i planted years ago helps enough we can see a noticeable difference by the good it is doing. Wish everyone had clover in with the brome but it takes a little longer to dry.

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