Difference between nitrate and ammonium nitrogen
- Thread starter jayjay777
- Start date
uptake of NH4 causes PH to drop, uptake of N03 causes PH to rise so it can be useful for ph control in recirculated systems. Typically, NH4 equates to less than 10% of the total N (90% nitrate) with dtw nutes but it can be a somewhat higher percentage for recirc and coco nutes. Urea is the one you dont want to see on a hydro nute label 
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jayjay777
Well-Known Member
Next years my first outdoor, I use to grow trees inside. Never grown outside before. I’ll be in a greenhouse with mini splits, a quest and burner.
I’m wasting 500 plant permit in Rockwool cubes when I could be doing trees... if I can do 16-24oz plants inside years ago, I imagine I can do 5-10lb trees outdoors.
I would like to stay comfortable with what I know, using coco/perlite mix in 30 gal pots, I guess my concern is salt buildup and burning. There going out as small bushes though, but I just figured my feedings should be lower outdoors, say 600ppm every watering since the evaporation rate is much faster. Opinions?
Pics of one of my rooms I’m planting today...
I’m wasting 500 plant permit in Rockwool cubes when I could be doing trees... if I can do 16-24oz plants inside years ago, I imagine I can do 5-10lb trees outdoors.
I would like to stay comfortable with what I know, using coco/perlite mix in 30 gal pots, I guess my concern is salt buildup and burning. There going out as small bushes though, but I just figured my feedings should be lower outdoors, say 600ppm every watering since the evaporation rate is much faster. Opinions?
Pics of one of my rooms I’m planting today...
MrPuffTuff
Active Member
Are those moms in the back right? If so you stripped them bare!
@jayjay777 if you are going outside soil on a large scale your best best is probably organic. It's sustainable and you can reuse the soil crop after crop. If you go synthetic eventually your going to need to replace the soil from salt build up.
Basically ammonia/ammonium is broken down by de-nitrifying bacteria into nitrites and finally nitrates. Most agree plants prefer nitrates and they are more readily available to the plants. Nitrates promote uptake of some cations unlike ammonium that competes. Agree with the shifting of PH as stated above and to add to that the PH has a direct effect on the form of ammonia/ammonium and vice versa. Its not recommended for hydro because of the general lack of de-nitrifying bacteria in our systems to break down ammonia/ammonium, this is not usually a problem in soil. I for one seed and use these bacteria but if you wait for them to develop on their own it's generally 5-6 weeks and you need to have ammonia/ammonium present in order to do so. There is a bit to learn about them before just seeding and forgetting.
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churchhaze
Well-Known Member
How about some synthetic organic urea?
churchhaze
Well-Known Member
Plants can take up ammonium directly and quickly use it as nitrogen, but at the cost of blocked potassium uptake (and other cations) which causes symptoms we know as N toxicity.
It can help regulate pH because of what atomizer said, but you will quickly run into problems if you add too much. (glossy green with the claw)
It can help regulate pH because of what atomizer said, but you will quickly run into problems if you add too much. (glossy green with the claw)
Urea would work for the nitrogen but what about the rest of it?
Yeah I have to show ID to buy it here and even then am limited to a small amount and that was almost 10 yrs ago
jayjay777
Well-Known Member
Googleable lmao
jayjay777
Well-Known Member
GH maxi series dry powder uses ammonium nitrate. I’m looking to test new product like canna A&B.
I was going to do trees in 100 gal pots of perlite/coco 70/30.
I feed 500ppm to moms, 300-500ppm to clones & veg and 600-1000 in flower. Every watering. Never had salt build up or burn issues in my coco grow which has been about 3 years now.
Besides maxigro n maxibloom, I use koolbloom, silica, hydrogaurd.
I actually airate the hydrogaurd and it makes more, just use distilled water...
I was going to do trees in 100 gal pots of perlite/coco 70/30.
I feed 500ppm to moms, 300-500ppm to clones & veg and 600-1000 in flower. Every watering. Never had salt build up or burn issues in my coco grow which has been about 3 years now.
Besides maxigro n maxibloom, I use koolbloom, silica, hydrogaurd.
I actually airate the hydrogaurd and it makes more, just use distilled water...
rkymtnman
Well-Known Member
when you get close to empty, check out southern ag garden friendly fungicide. same strain, million times stronger and cheaper
Chris Edward
Well-Known Member
If the outdoor grow is going to be in pots, then use calcium nitrate.
The calcium nitrate will wash through the soil before it becomes a problem, in the pots anyway...
If the outdoor grow is going to be in the ground or raised beds, then use 50:50 calcium nitrate:ammonium sulfate.
This is because the calcium nitrate will get used first and any subsequent nitrate will flow deeper into the soil out of the roots range. The ammonium sulfate will also wash out a little as well but it will remain within the roots range, so it will encourage the roots to grow longer, thus taller plants.
Plus the 50:50 calcium nitrate:ammonium sulfate is a good choice to use during flower, because the plants can still get all the nitrogen they need, but the calcium will be reduced so it won't mess with flower production. You can play around with the ratio of calcium nitrate to ammonium nitrate for your specific strain, because some strains are more sensitive to calcium during flower than others.
Also because ammonium sulfate has an N-P-K of 21-0-0, you don't have to use as much, about 73.8% as much as calcium nitrate (15.5-0-0) and ammonium sulfate tends to cost less as well.
As far as ammonium in hydro, if it's an older system and you don't wash your reservoirs out with bleach or scrub them too much between grows, then there's a good chance you have a healthy population of nitrosomonas (ammonia to nitrite) and nitrobacter (nitrite to nitrate) bacteria which will convert the ammonia to nitrate PDQ.
One other thing you may want to consider for an outdoor grow is green manure.
This can be planted under and around the cannabis and the plants will shade the ground so (other) weeds don't grow. If you use a plant like white clover, this will actually fix nitrogen from the air, so it will cut down a little on the nitrogen you will need for your grows.
I hope that was helpful.