Ammonium Sulfate 21-0-0 Uses

[whoose]

Dixondale (the onion place) says to use Ammonium Sulfate 21-0-0 on their onion plants they are sending me next week. Any special considerations with using this fert?

Are there any other uses with different vegetables?

Pro's and con's please

[GaryStPaul]

I ran across a reference to ammonium sulfate 21-0-0 for use on tomatoes (Colorado, master gardener program):

http://www.ext.colostate.edu/mg/Gard...#fertilization

I've never done this myself and was frankly surprised to see the recommendation. Perhaps others can comment.

Gary

[PaulF]

I applied Ammonium Sulfate to my garden in addition to Elemental Sulphur to reduce pH and increase nitrogen. All according to soil test results. Time will tell if this was a good move.

[TomNJ]

It is a good source of nitrogen, so it will benefit any vegetables that like rich nitrogen. Usually these are leafy greens, but also includes onions and garlic as you want to grow the green and let the green feed the bulbs. For garlic you want to stop feeding in mid May, and onions when they start to bulb.

TomNJVA

[Worth1]

Originally Posted by whoose

Dixondale (the onion place) says to use Ammonium Sulfate 21-0-0 on their onion plants they are sending me next week. Any special considerations with using this fert?

Are there any other uses with different vegetables?

Pro's and con's please

That is fine you just want to make sure you have P an K for root growth.

Worth

[PureHarvest]

I thought adding sulfur makes onions pungent/hot?

From vidaliaonion.org

"3. Low sulfur soils that keep the bulbs from developing a pungent taste. Regular onions derive their hot taste from sulfur-containing compounds. It’s these compounds that eventually make you cry when you cut them"

And:
Soil
"Must be sandy enough to let sulfur wash through to the clay below. Sulfur is what makes onions hot and pungent, so low sulfur creates mild, sweet onions. In South Georgia, we receive about 50 inches of rain annually, which helps leach sulfur out of the sandy root zone."

[Gardeneer]

My soil test shows abundance of P and K but deficiency of N and S.
Ammonium sulfate should take care of both.
Most all purpose fertilizers (like 16-16-16) have Ammonium Sulfate as Nitrogen source.
MG blue stuff is also very high on Nitrogen ( 24-8-16).

Back to Gary's comment:
Early in the season tomatoes would appreciate more Nitrogen to develop as a prelude to flowering and fruiting.
The thing with Nitrogen is that being readily water soluble, it won't stick around like P and K.
Gardeneer

[PureHarvest]

Originally Posted by GaryStPaul

I ran across a reference to ammonium sulfate 21-0-0 for use on tomatoes (Colorado, master gardener program):

http://www.ext.colostate.edu/mg/Gard...#fertilization

I've never done this myself and was frankly surprised to see the recommendation. Perhaps others can comment.

Gary

It has 24% sulfur! I would want to know what my soil had in total elements before adding that much sulfur.

Not sure how they can recommend that without knowing more about your soil needs.
I think they are focusing on the 21% Nitrogen, which is fine, but to disregard the 24% S might be bad depending on your existing soil's elemental balance.

[PureHarvest]

Originally Posted by Gardeneer

My soil test shows abundance of P and K but deficiency of N and S.
Ammonium sulfate should take care of both.
Most all purpose fertilizers (like 16-16-16) have Ammonium Sulfate as Nitrogen source.
MG blue stuff is also very high on Nitrogen ( 24-8-16).

Back to Gary's comment:
Early in the season tomatoes would appreciate more Nitrogen to develop as a prelude to flowering and fruiting.
The thing with Nitrogen is that being readily water soluble, it won't stick around like P and K.
Gardeneer

I have never seen a general purpose fert with ammonium sulfate as the nitrogen source. Which brand do you use?
Gen purpose is almost always ammonium nitrate and urea.

[Gardeneer]

Originally Posted by PureHarvest

I have never seen a general purpose fert with ammonium sulfate as the nitrogen source. Which brand do you use?
Gen purpose is almost always ammonium nitrate and urea.

I think it is Lilly Miller. Not sure. I will check it tomorrow.
But I think I have some 21-0-0 left too. Otherwise I have to get another bag of it.

Gardeneer.

[berryman]

I use it when making compost. My soil is so very alkaline and the sulfur in the fertilizer helps acidify.
I have some Korean nut pines and a bunch of other plants that will not thrive unless I add the acidified compost.
Lily Miller makes (sells) it and also IFA stores in the intermountain west sell it in bulk. Farmers spread it here by the ton.

[AKmark]

This is a great read that explains the difference in ammoniacal Nitrogen and nitrate Nitrogen, what they do, and why.

http://www.greenhouse.cornell.edu/cr...rogen_form.pdf

[zeroma]

It has been recommended to me by the lab that did the soil analysis (I called them to find out what N source to use) for our community garden. We have high pH from 7.7 in our best beds all the way up to 8.2. That's what was suggested as the N source to help lower pH. The actual soil analysis included information on how much sulphur to add. One of the beds, the one I planned to grow zucchini and other squ) ash said it needed 25# of sulphur per 1000 sq feet to reduce the pH to the optimal 6.5. But not to exceed more than 5# per 1000 sq feet in one year. So when you do the math and have a smaller (or larger number of sq ft) it gets tricky to understand. for that bed we are supposed to use just 1.75# due to these considerations.

You first need to know what your soil is before you can choose the best fertilizer. You need to know if you have a heavy clay soil or a sandy soil because they each have their own set of considerations. Oh, and don't forget, if you have a high percent of organic matter, you need less sulphur. If you have low percent of organic matter in your garden, you need more sulphur. This is all for high pH, not for soils that are acidic. For that you need lime and it is much easier to adjust your soils for raising your pH...................

I'm working at getting a good grasp of pH and all the science of it, to know how best to use all the amendments available out there to buy. Of course, you real farmers likely already know all that.


So even though tomatoes or other plants my be heavy feeders of nitrogen, you still need to know your own soil has to offer before just willy nilly adding chemicals and wrecking either your plants by burning them, or the environment by using way too much and just wasting money all at the same time.

Oh and just one more aside: For tomatoes, they like to eat their N at first cluster. Peppers like to eat their N at first fruit set so you do side dressings rather than just dropping/broadcasting N pre planting. (The way I've almost always done because that is the way my mom did it.)

Soil tests really tell you a lot of information. Can you tell I'm a fan of doing a soil test from a reputable lab?

zeroma

[PureHarvest]

Funny about the regional differences.
You would never find ammo sulfate around here unless you special ordered it. I'm sure the pH worshipers order it for blueberries though.

Zeroma, good for you on taking the time to test and trying to understand what you are doing and why. We can't manage what we don't measure.

[AKmark]

Zeroma, I think N need picks up after the formation of the first fruits, actually quite a lot.