What types of nitrogen fertilizers are effective: nitrate, ammonium or amide?

[proninyaroslav]

Hi everyone. Not so long ago I thought: there are several types of chemical nitrogen fertilizers - nitrate, ammonium and amide (e.g carbamide).
But which of them/how is their combination most effective and fast for trees in inorganic soil conditions, if we set the goal of getting a big growth (development of primary and secondary branches, trunk)?

 

[WNC Bonsai]

Since plants convert nitrogen into amino based molecules (NHx) they energetically benefit most from amonia nitrogen (NH4) as it can be more directly incorporated into the amino group. Other forms of nitrogen such as nitrate (NO3) have to be converted to be incorporated into the amino group in an extra step which takes energy. That is why farmers typically apply nitrogen as hydrated ammonia. However applying ammonia is acidifying which is why they apply granular limestone to neutralize that acidity. This is also why fertlilizers for acid loving plants such as azaleas have more nitrogen as amonia molecules.

 

[proninyaroslav]

Since plants convert nitrogen into amino based molecules (NHx) they energetically benefit most from amonia nitrogen (NH4) as it can be more directly incorporated into the amino group. Other forms of nitrogen such as nitrate (NO3) have to be converted to be incorporated into the amino group in an extra step which takes energy. That is why farmers typically apply nitrogen as hydrated ammonia. However applying ammonia is acidifying which is why they apply granular limestone to neutralize that acidity. This is also why fertlilizers for acid loving plants such as azaleas have more nitrogen as amonia molecules.

What about carbamide (urea) as an addition? I have three fertilizer options, which one is the best (or none):

1. 14:10:28 (nitrate and ammonia nitrogen are about equal)
2. 19:6:20 (~12% nitrate and 7% ammonia)
3. 18:18:18 (~4% nitrate, 12% carbamide and 2% ammonia)

 

[BrightsideB]

I’m sure it has been done but would be cool to see an experiment using the different types used for several years on seedlings of the same species of tree’s.

 

[proninyaroslav]

@RKMcGinnis
I tried to look for similar information, but maybe I searched badly)

 

[BrightsideB]

I only use organic right now. When I get my place in a few more years. I am going to be doing a lot more experiments. This is going to one of them.
a user on this forum @cmeg1 posts turned me on to using the fulvic and humic acids and the results were easy to see. I started pouring humic acid in my garden a few times a week with the fertilizer and results were really good vegetables tasted great. And my tree’s thrive more as well.

 

[WNC Bonsai]

Urea is another common balanced commercial fertliizer component. It contains nitrogen in organic molecues which have to be broken down by soil bacteria in a process called mineralization and then converted to amonia via ammonification then is taken up by plants. So with a balanced fertliizer your plants get an initial pulse of nitrogen from the ammonia and then a delayed release from the urea. The problem with liquid fertliizer is most of the excess nitrogen not immediately taken up by bonsai gets flushed out by watering long before the urea can be mineralized and taken up. That is why I use a solid fertliizer for slower release as it stay around long enough for the bacteria to do their thing. I also apply some liquid fertlizer in diluted amounts for the quick fix. I am now using GroPower solids and Miracle Grow liquid.

I use Gro Power solid with 12% N which has a combination of solube urea and insoluble N which is released over a 12 month period. For the liquid I use Miracle Gro which also is a combination of ammonia and urea. The main difference between the standard N=24% and acidic N=30% Miracle Grow is the second has more as urea.

The approach you use needs to take into account whether you want to use both a solid and a liquid and what kind of acid loving plants you have that need a more acidic soil. I think I might use the 18:18:18 myself if that was all I had access to. However a handful of dry chicken manure sprinkled on the soil surface once a year would be a good addition.

 

[Wires_Guy_wires]

@RKMcGinnis
I tried to look for similar information, but maybe I searched badly)

Look for in vitro propagation for your plant on google scholar, they do this propagation in large numbers with small differences in medium nutrient and hormone composition to figure out whats best for one plant species. If it works in a petri dish, it works in a pot. Because it's the water that transports the nutrients, not the medium itself. Petri dish gelling agents are meant to be 'as inert as possible', kind of like our inorganic bonsai soils.

Murashige & Skoog salts for instance are fairly balanced. Other formulations like [Insert name] Woody Plant Medium or Gamborg B5 for instance, have different amounts of additives and nutrient compositions. For most nursery plants this has been worked out and you can fetch a recipe name from a review paper or an abstract without having full access.

I've done a couple of those studies myself and I can fairly sure say that it's a whole lot of work. Imagine doing 400 cuttings, every day.
And then photographing all of them from multiple angles, count the roots, root branching, shoots, buds and growth pattern, log it in an excel sheet.. and doing the same thing the next day. And the next. And the next. Repeat for three months.
If you ever wonder where I started going crazy, it wasn't that time, but it surely contributed.

The story of Murashige & Skoog is fun to read, very scientific but imagine two very intelligent guys trying to look for new hormones and accidentally figure out how to optimize growing tobacco in a petri dish by trying different formulations with micrograms of difference between one another, and then tweaking it another 100 times. And then doing it again all over a couple time just for the sake of it. Most plant nutrient producers start off with this general MS formulation and tweak it from there. As a matter of fact, some of them copy it to the T without the sugars. A couple years ago I did an analysis of consumer available nutrients and the ones that came out the best had a large overlap with the murashige & skoog formulation.

A dutch company called Duchefa has a catalogue in pdf format (English) which contains the most commonly used formulations and their composition. They also have pretty extensive information about nutrients, hormones, chemicals and their effects in that catalogue. Surely worth a read, even if you don't know a thing about tissue culture or laboratories. I skim through it every six months just to see if there's something new in there that's worth investigating.

Murashige and Skoog medium - Wikipedia

en.m.wikipedia.org

http://brochure.duchefa-biochemie.com/Duchefa_catalogus_2010_2012/

 

[cmeg1]

Ammonium no more than 10% I belive.The first 2-3 weeks of a seedlings life an extra pinch(1/16/1/8th tsp) monoAMMONIUM phosphate can give an extra 20% more roots from the start which is very beneficial if all othe growing environment elements are in check.

Only first 2-3 weeks as the ammonium form will cause a cal mag deficiency inevitably…..a serius epic fail.

Ammonium is the only form of nitrogen safe for foliar…NITRATE WAAay to powerful for leaves.
Ammonium can cure a nitrogen deficiency through a foliar application in literally hours after applicaTion.
Nitrate is preferred for hydro( volcanic/inert substrate) ……this is essentially drain to waste hydroponics!!!!
I prefer adding calmag since I use RO /pure water.
These are the only forms I am familier with.

 

[WNC Bonsai]

The Duchefa publication is a really good overview, thanks for the link.

 

[WNC Bonsai]

Ammonium no more than 10% I belive.The first 2-3 weeks of a seedlings life an extra pinch(1/16/1/8th tsp) monoAMMONIUM phosphate can give an extra 20% more roots from the start which is very beneficial if all othe growing environment elements are in check.

Only first 2-3 weeks as the ammonium form will cause a cal mag deficiency inevitably…..a serius epic fail.

Ammonium is the only form of nitrogen safe for foliar…NITRATE WAAay to powerful for leaves.
Ammonium can cure a nitrogen deficiency through a foliar application in literally hours after applicaTion.
Nitrate is preferred for hydro( volcanic/inert substrate) ……this is essentially drain to waste hydroponics!!!!
I prefer adding calmag since I use RO /pure water.
These are the only forms I am familier with.

Yes a big problem with ammonium is toxicity as well as pH, it has to be applied in just the right amount or it can cause issues. When applied as urea it basically is slowly converted to ammonium and released to the plants. The saving grace when it comes to bonsai culture is whatever the plants don’t take up larlgey ends up on the ground. However since it is a cation it will be retained on CEC surfaces. Nitrate on the other hand is an anion and highly mobile in soils so is not retained to any significant degree.