Any ideas as to what this is?

[kman]

Note the basicity of the material we use. Our water has very low alkalinity and the hardness that is present is from Mg.

 

[southernbelle]

I have two nutrient solutions that must be made in 100% tap water to reach a pH of 6.3. Another solution needs 15-20% tap water to reach 5.8. Two other solutions must be in 100% RO to reach 6.4 and 6.0. You have to test your solutions. Most city tap water will raise the pH and perhaps add some extra nutrients (Ca, Mg, Si).

Terry I use RO and have used MSU for a few years. The question is urea nitrogen. Should I incorporate it? I’ll email you.

 

[Ray]

If there is an issue with the solutions applied, it's likely not related to the pH per se, but to the acidity or basicity, which can have a long-term effect on rhizosphere pH, not an immediate one.

 

[terryros]

If there is an issue with the solutions applied, it's likely not related to the pH per se, but to the acidity or basicity, which can have a long-term effect on rhizosphere pH, not an immediate one.

I agree, Ray. I think the potting media also matters.

 

[terryros]

Terry I use RO and have used MSU for a few years. The question is urea nitrogen. Should I incorporate it? I’ll email you.

There isn’t certainty about most of this. I decided to give up and use some of each of the major approaches - a complete hedge. This is unlikely to be the best approach, but I don’t have 20 years left to experiment!

 

[skirincich]

Any suggestions on how much urea should be dissolved per gallon of water?

 

[kman]

How strong a solution you want to use, I can't say. But about 0.38 grams in 1 gallon of water = 100 PPM N.

Volume doesn't work measuring urea as the from factor varies. You have to weigh it.

 

[Ray]

Any suggestions on how much urea should be dissolved per gallon of water?

The stuff is 46%N, which is 460,000 ppm or mg/kg. If you're shooting for 100 ppm N, then that would be 1000g/4600= 0.217g x 3.785 = 0.822 g/gal.

 

[CharlesD]

Terry I use RO and have used MSU for a few years. The question is urea nitrogen. Should I incorporate it? I’ll email you.

I’ve been using southern ag max acid 30-10-10 which you can get in Amazon 22% urea, 5% ammonia, 2% nitrate so it’s not 100% urea like jack’s. I would think you could try rotating it every once in a while. Though I would recommend mixing fertilizer with some tap water for the buffering effect unless your tap water is super hard.

 

[kman]

The stuff is 46%N, which is 460,000 ppm or mg/kg. If you're shooting for 100 ppm N, then that would be 1000g/4600= 0.217g x 3.785 = 0.822 g/gal.

I stand corrected, Ray. I didn't take into account the 46%.

 

[Ray]

HAH! No need for an apology. I was questioning my own calculations, while drinking my first cup of coffee this morning.

 

[Canadienne]

I’ve cut it off and repotted. Will douse with fungicide and bactericide.

This summer I had 3 phrags that broke out with similar brown patches as yours. It was warm and humid, showed up overnight. Realizing it was likely bacterial, the only thing I had on hand was polysporin. ( for human use, a topical ointment) It has bacitracin and gramicidin in it. Stopped the infection cold. Available in drugstores. Worked for me like a charm. Hope you were able to salvage your plants.