Author Topic: Urea Spray  (Read 1904 times)

Millet

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Urea Spray
« on: December 14, 2021, 06:26:06 PM »
Tomorrow is December 15, which is two and a half months before citrus flowering.  Therefore, tomorrow is the day to spay the foliage with the first urea spray to induce a better bloom, thus a better crop.  I did not spray last year and the crop was less than usual. 

poncirsguy

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Re: Urea Spray
« Reply #1 on: December 14, 2021, 07:51:24 PM »
would spraying with diluted urine serve the same purpose.

hornad

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Re: Urea Spray
« Reply #2 on: December 14, 2021, 10:38:11 PM »
would spraying with diluted urine serve the same purpose.
Yes, and it would give a wonderful smell to your orchard!

pagnr

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Re: Urea Spray
« Reply #3 on: December 15, 2021, 04:51:12 AM »
would spraying with diluted urine serve the same purpose. ??

Just exactly what "equipment'' are you using ??

poncirsguy

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Re: Urea Spray
« Reply #4 on: December 15, 2021, 12:21:35 PM »
Pump sprayer 1 gallon from Home Depot. adjustable mist.  Urine is premix by drinking excessive water before collecting.

Galatians522

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Re: Urea Spray
« Reply #5 on: December 15, 2021, 10:10:00 PM »
A quick chemical analysis shows that undiluted urine typically has only about 2/3 the actual nitrogen content of the recommended urea spray. Average urine contains 7.75 lbs urea /100gal vs. 11.5lbs/100gal for low biuret urea spray (based on the information that I found). Also, salt content would likely be very high in urine by comparison. Beyond the simple chemestry, one of my great joys in gardening is being able to share what I produce with others. The list of people interested in sharing produce treated with human waste is rather short.

hardyvermont

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Re: Urea Spray
« Reply #6 on: December 16, 2021, 10:47:34 AM »
Is there enough biuret in urine to be a concern?

luak

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Re: Urea Spray
« Reply #7 on: December 16, 2021, 03:29:43 PM »
Going back to the Stone Age or maybe the Far Far Far East. I don’t even let my dog p…..and p…..p in my garden.

poncirsguy

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Re: Urea Spray
« Reply #8 on: December 16, 2021, 03:40:18 PM »
I currently have 50 pounds of ammonia sulphate and have 0 pounds of low biuret urea.  is ammonia sulphate just as good.
My kumquat trees flower in early summer.  Should I wait till May 1st before spraying?

pagnr

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Re: Urea Spray
« Reply #9 on: December 16, 2021, 03:57:49 PM »
Personally, I don't think there are health concerns using urine for plants. It is essentially sterile.
It has emergency medical uses, with mid stream urine, i.e. suburn, as urea itself is skin moisturising.
As Galatians said, the N Urea content of Urine is far lower than Fertiliser urea, so it can't be used to make the equivalent concentration sprays.
That said, fertiliser Urea has a lot of problems with loss of N to the atmosphere, so often the effective ammount the plants can get is lower than that applied.
Not sure if more frequent low % urine sprays will give the boost of the the N fertiliser Urea spray.
Biuret is produced by heating Urea in the manufacturing process, so shouldn't be a problem in Urine.
I have used diluted urine to feed weak plants or very small seedlings that I didn't want to risk with stronger fertilisers.
Also had some Citron seedlings with what looked like Biuret problems from fertiliser in old potting mix.
It seemed to correct them, possibly by gently lowering the Biuret %  in the mix ??

Millet

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Re: Urea Spray
« Reply #10 on: December 16, 2021, 06:06:19 PM »
Nutrients when used as a foliar spray can only be absorbed into the leaf when they are in the liquid state.  After the nutrient dries on the leaf surface, it is no longer available.  Urea is extremely hydroscopic and will resolubilize on the leaf surface each time the humidity again rises. This is why Urea provides more nitrogen  through foliar spray then other forms of N. University of California at Riverside only recommends Urea foliar spray for a better flower bloom.

Tortuga

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Re: Urea Spray
« Reply #11 on: December 16, 2021, 06:52:54 PM »
Interesting. I think I will follow your lead Millet.

In the fall through early spring I always wee in my garden. What is so different from using excrements from a human and a/an (insert grazing animal here)

Galatians522

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Re: Urea Spray
« Reply #12 on: December 16, 2021, 10:52:18 PM »
Nutrients when used as a foliar spray can only be absorbed into the leaf when they are in the liquid state.  After the nutrient dries on the leaf surface, it is no longer available.  Urea is extremely hydroscopic and will resolubilize on the leaf surface each time the humidity again rises. This is why Urea provides more nitrogen  through foliar spray then other forms of N. University of California at Riverside only recommends Urea foliar spray for a better flower bloom.

I did not know this about urea, very informative.

Galatians522

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pagnr

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Re: Urea Spray
« Reply #14 on: December 17, 2021, 07:16:47 AM »
Going back to the Stone Age or maybe the Far Far Far East...

Or 1500's to 1600's England, where the straw covered dirt floors of commoners houses, horse stables etc were the source of saltpetre for gunpowder.
This resource belonged to the monarch, and was collected by saltpetre men, often in a destructive or disruptive manner.
https://reviews.history.ac.uk/review/1481

poncirsguy

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Re: Urea Spray
« Reply #15 on: December 17, 2021, 10:09:19 AM »

CarolinaZone

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Re: Urea Spray
« Reply #16 on: December 17, 2021, 11:48:36 AM »
Is this an all zones recommendation? I just got the last of my fruits off the tree.  Won't it stimulate new growth that will just get damaged in the next 2 months?

Millet

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Re: Urea Spray
« Reply #17 on: December 17, 2021, 01:49:17 PM »
CarolinaZone, you brought up a good point.  The low biuret urea spray is for warm zones and for areas where the tree is sheltered in a warm area during the winter, such as a greenhouse, or home. 

Millet

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Re: Urea Spray
« Reply #18 on: December 20, 2021, 01:14:48 PM »
I finally got my trees sprayed with low biuret urea yesterday.  Further, all this winter I have set my greenhouse nighttime temperature down to a low of 40F.  Low temperatures, called cold hours, greatly aid in producing a strong bloom.  The sate of Florida keeps track of the amount of cold hours, and advises Florida's citrus growers weekly on their accumulation, which helps the growers to estimate the strength of the bloom and thus the size of the crop to be expected.
« Last Edit: December 20, 2021, 01:18:41 PM by Millet »

luak

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Re: Urea Spray
« Reply #19 on: December 20, 2021, 09:18:41 PM »
Millet, at least you can control temps in your greenhouse, I can . My growroom is part of the house heating system, set at 65 in that room. Lights are on between 7am and 7pm. Urea might work, I use it but don’t know if it works for me. Most of my citrus and avocado and Jaboticaba are heavy blooming now. Most of my citrus have a lot of fruits on them.





« Last Edit: December 22, 2021, 11:13:37 AM by luak »

Lovetoplant

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Re: Urea Spray
« Reply #20 on: December 20, 2021, 11:43:27 PM »
Tomorrow is December 15, which is two and a half months before citrus flowering.  Therefore, tomorrow is the day to spay the foliage with the first urea spray to induce a better bloom, thus a better crop.  I did not spray last year and the crop was less than usual.

Millet, most of my tangerines, and navel are still hanging on the trees.  Could I spray the trees with LB urea? 
From what I read on the net, spraying the trees with nitrogen with turn the fruits more acidic.