Foliar N

[Steevo]

I usually top up my wheat crops with their last bit of N around flag leaf timing, but looking at the forecast, there's no rain due for over a week. Looks like the season has turned from soaking wet and muddy to bone dry and cracks everywhere.

It's got me thinking if I'd be better to mix the solid into liquid, and apply that as foliar N through the sprayer with the idea of it being taken in through the leaf. I did consider applying as liquid through liquid fert nozzles but having never done that before and the warm temps and glaring sun forecast I thought it might be too big a risk of scorch.

Is it worth doing it as foliar, or am I barking up the wrong tree?



The crop will have a Nufol protein spray as usual around the beginning of July on top as well as is standard in previous years.

 

[Lothian]

It works but don't expect some magic 9:1 efficiency ratio in my experience. If you put on 8kg N work on that being all you get. It helps if you up the water rate to 200l/ha to avoid scorch too
/

 

[Andrew K]

How much top up N are we talking?
I would use N 20 at 200 l/ha on a cool still evening to get around 40kg/ha on, but be wary of scorchy conditions.

 

[PSQ]

I would use N 20 at 200 l/ha on a cool still evening to get around 40kg/ha on, but be wary of scorchy conditions.

Does anyone mix in a bit of T3 fungicide with their foliar?
I'm thinking 100L of N20 (Urea) with 50L water to make 150L/ha, and a bit of left over prothio / other 'azole?

 

[Steevo]

It works but don't expect some magic 9:1 efficiency ratio in my experience. If you put on 8kg N work on that being all you get. It helps if you up the water rate to 200l/ha to avoid scorch too
/

Thank you. That's all I would be expecting - just replacing the fert I spin on with fert through a nozzle.

How much top up N are we talking?
I would use N 20 at 200 l/ha on a cool still evening to get around 40kg/ha on, but be wary of scorchy conditions.

Good question that. Wheats are so far up to around 140-160kgN. Aiming for milling but this heatwave/drought has completely caught me out after struggling to travel a couple of weeks ago and no rain forecast for 10 days or so. I'm getting concerned that I won't hit milling without sufficient N in the plant in the time available.

Through the spinner I'd have applied another 75kgN I think, with the protein top up 200l of N20 for 40kgN after.

I'm considering whether to apply 200l N20 now, and then perhaps follow up with the protein spray in a month or so. It's all new to me putting N in via the leaf - though I routinely do manganese/magnesium etc. that way.

Does anyone mix in a bit of T3 fungicide with their foliar?
I'm thinking 100L of N20 (Urea) with 50L water to make 150L/ha, and a bit of left over prothio / other 'azole?

Now that is an interesting question to ask! You've potentially saved me a pass with this logic. Might have to quiz my agonomist about whether he'd be happy with N20 as a carrier for the fungicide.

 

[Steevo]

Decision made - first batch in the mixing tank now ready for application tomorrow evening.

 

[Old apprentice]

Would some molasses in the mix make it less likely to scorch.

 

[Headless chicken]

Would some molasses in the mix make it less likely to scorch.

Yes and improve efficiency

 

[vantage]

Yes and improve efficiency

And some Mag flake to keep it on the leaf longer.

 

[Steevo]

Does anyone mix in a bit of T3 fungicide with their foliar?
I'm thinking 100L of N20 (Urea) with 50L water to make 150L/ha, and a bit of left over prothio / other 'azole?

Anyone else with further thoughts on this?

 

[PSQ]

Anyone else with further thoughts on this?

Agronomist meeting tomorrow. I'm thinking of adding 13k.5kg urea (6.22kgN) in to the mix, with bitter salts, a bit of left over K2SO4 and a bit of azole. It shouldn't be ready to go for a while yet, but I'd like to try a tramline ASAP and leave it for a week before spraying the rest at the correct timing. At that point I'll miss the N out on one tramline, and spray the test tramline again, and at harvest measure yield and quality to see if it's worth repeating.
This N concentration is less than a 3rd of what would go on as straight N liquid urea.



[1.8t x 460kgN = 828kgN.
828 / 133ha = 6.22kgN/ha.]

 

[Headless chicken]

Anyone else with further thoughts on this?

No reason why not but I’m not an agronomist. I’d use fulvates in order to get a better uptake of chemical regularly

 

[eagleye]

definately late, cool evening to speed uptake and reduce scorch risk

 

[Steevo]

definately late, cool evening to speed uptake and reduce scorch risk

Thanks. Got 8000l sprayed yesterday evening and another 4000l done this evening.

Feels like a slow way to spread 3 bags of fert each sprayer tankful compared to the spreader but hopefully will be doing the job that’s needed and that’s what’s important. Can spray a tank in about an hour and a half - 100l/min spot out the boom soon empties it.

Second batch of liquid is in the mixer now ready for tomorrow.

 

[JCfarmer]

Thanks. Got 8000l sprayed yesterday evening and another 4000l done this evening.

Feels like a slow way to spread 3 bags of fert each sprayer tankful compared to the spreader but hopefully will be doing the job that’s needed and that’s what’s important. Can spray a tank in about an hour and a half - 100l/min spot out the boom soon empties it.

Second batch of liquid is in the mixer now ready for tomorrow.

Is it not a bit early for a protein spray?

 

[Steevo]

Is it not a bit early for a protein spray?

Yes.

I’m just trying to get some N into the plant that it should have and I cannot do with solid fert as there is no rain forecast for at least another 10 days.

Protein spray will be going on in a month or so.

 

[Steevo]

Looking at fields sprayed on Monday evening there is a slight bit of tipping on the leaf like epoxy fungicide used to do.

Not sure if that’s caused by the wind, it’s certainly not been hot or direct sunshine in the evening when I have been applying.

Either way it looks to me like it’s a result of the N getting into the leaf and rushing to the tip. If so it’s a good thing that the N is in the plant, even if it’s caused some minor leaf damage.

 

[Old apprentice]

Looking at fields sprayed on Monday evening there is a slight bit of tipping on the leaf like epoxy fungicide used to do.

Not sure if that’s caused by the wind, it’s certainly not been hot or direct sunshine in the evening when I have been applying.

Either way it looks to me like it’s a result of the N getting into the leaf and rushing to the tip. If so it’s a good thing that the N is in the plant, even if it’s caused some minor leaf damage.

Any photos of the crop that you are concerned it needs n.

 

[Steevo]

I can get some tomorrow.

It’s Skyfall that was intended to be grown for milling potential so I don’t want to miss out on milling premium if it can be avoided. Current 140-160kgN wouldn’t be enough for the protein level needed even with a protein spray in early July.

 

[DrWazzock]

I was just wondering. I’ve 200 litres of liquid N fert 30 left over from a few years back. If I spray it on my OSR at 20 litres per ha in 200 litres per ha will it scorch? I’m also adding in 3 litres bortrac and 2.5 kg bittersalz. We used to spray on oilseed extra which was something like 20% N at a rate of 200 l per ha plus 100 litres water so I’d have thought what I was doing was safe enough at that low conc but maybe the oilseed extra had some antiscorch additive. Sick of looking at these two 200 litre drums of N30 and trying to put them to good use.