Does too much Nitrogen lock out Phosphorous?

weedstoner420

Well-Known Member
I check my ph before every watering with the standard yellow meter (cheap, but not total garbage). I always need to bring it down from 8+ with some organic granulated citric acid. Maybe it's time I calibrated the meter?

Regarding the Cal-Mag, I've been using Roots Organic Elemental and have been giving it 2 tbsp every week. I'm in a 5 gallon pot, but I wonder if that's too much now that I see the Mulders chart.
That sounds like a lot of cal-mag. Are you sure you even need to be adding it at all?
 

jimbonorman

Well-Known Member
That sounds like a lot of cal-mag. Are you sure you even need to be adding it at all?
No, I'm definitely not sure that I need to be adding that much. I have a bad habit of giving plants more than I should. I see all these folks growing monster colas using 10 different bottles of nutes, etc. and I'm trying to compete with organic top-dressing...it often gets me into trouble. At this point I'm wondering if I need to just do straight water for 2 weeks...
 

jimbonorman

Well-Known Member
On the other hand...I've got a Dougs Varin that's been doing just fine with the exact same regimen, so I've been leaning toward this being a particular sensitivity with the Malawi...plus there's this bit of advice on the Ace Seeds Malawi page:

We recommend moderate nutrients levels during the growing stage (slightly low of nitrogen) and moderate-high for the flowering stage.

...so I've assumed it's been too much N for the Malawi but not so much for the DV ‍
 

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PadawanWarrior

Well-Known Member
do you have any recommendations for good soil ph meters? Would suggest measuring run-off and soil, or just soil ph?
Good soil meters aren't cheap. You can do a slurry test with soil and distilled water for an estimate though if you want. More info would help, like your water supply, nutes, and media.
 

jimbonorman

Well-Known Member
Good soil meters aren't cheap. You can do a slurry test with soil and distilled water for an estimate though if you want. More info would help, like your water supply, nutes, and media.
water supply is city tap. always leave it out for 24+ hrs to burn off any chlorine

Nutrients I have been using are Down to Earth 4-8-4 (since flipping to flower) and Roots Organic Elemental. Mind you, I've been trying something different this run and it's possibly what's gotten me into trouble...instead of top-dressing with 2 tbsp per gallon every 4-5 weeks, I've cut that into fourths and been top-dressing once a week (2 tbsp of both DtE and Roots per week in 5 gallon pots).

Media is 60% FFOF, 20% EWC and 20% perlite
 

PadawanWarrior

Well-Known Member
water supply is city tap. always leave it out for 24+ hrs to burn off any chlorine

Nutrients I have been using are Down to Earth 4-8-4 (since flipping to flower) and Roots Organic Elemental. Mind you, I've been trying something different this run and it's possibly what's gotten me into trouble...instead of top-dressing with 2 tbsp per gallon every 4-5 weeks, I've cut that into fourths and been top-dressing once a week (2 tbsp of both DtE and Roots per week in 5 gallon pots).

Media is 60% FFOF, 20% EWC and 20% perlite
I'd cut out the Roots Organic CalMag and see if it gets better. Too much Ca has caused my leaves to twist like that a little too, and what fixed it was trying to up the Mg and lower the Ca. Too much Ca causes all kinds of issues. The DTE 4-8-4 already has plenty Ca as it is and who knows how much your water already has.
 

weedstoner420

Well-Known Member
No, I'm definitely not sure that I need to be adding that much. I have a bad habit of giving plants more than I should. I see all these folks growing monster colas using 10 different bottles of nutes, etc. and I'm trying to compete with organic top-dressing...it often gets me into trouble. At this point I'm wondering if I need to just do straight water for 2 weeks...
More is not necessarily better with nutrients, it's about having a good balance. Especially in organics.

It's for sure possible to grow monster colas using only organic top-dressings. Keep the plants healthy and give them plenty of light, and the colas will happen, especially with that Malawi (or so I have heard...)
 

jimbonorman

Well-Known Member
I'd cut out the Roots Organic CalMag and see if it gets better. Too much Ca has caused my leaves to twist like that a little too, and what fixed it was trying to up the Mg and lower the Ca. Too much Ca causes all kinds of issues. The DTE 4-8-4 already has plenty Ca as it is and who knows how much your water already has.
Thanks - I will def give this a shot and see what happens.
 

weedstoner420

Well-Known Member
water supply is city tap. always leave it out for 24+ hrs to burn off any chlorine

Nutrients I have been using are Down to Earth 4-8-4 (since flipping to flower) and Roots Organic Elemental. Mind you, I've been trying something different this run and it's possibly what's gotten me into trouble...instead of top-dressing with 2 tbsp per gallon every 4-5 weeks, I've cut that into fourths and been top-dressing once a week (2 tbsp of both DtE and Roots per week in 5 gallon pots).

Media is 60% FFOF, 20% EWC and 20% perlite
I hadn't heard of that 4-8-4 so I looked it up. It's 2% magnesium already. They don't mention calcium on the label, but the first ingredient is fish bone meal, so it's definitely got calcium from that. I would say supplemental cal mag is probably unnecessary.

Ugh, so annoying when they don't put the full nutrient analysis on the label. I can understand not putting all the micronutrients but they could at least put calcium, magnesium, and sulfur...

Depending on how much you added to your initial mix, your top-dressing rates don't seem out of line with the manufacturer recommendations (I usually go with the "vegetable and herb" rate if they specify).
 

1212ham

Well-Known Member
She did have one or two days that breached 80 degrees in the tent but that was about a month ago and she didn’t like that, but I didn’t witness a long-standing disruption as a result of that…
Low to mid 80s is best with led. Unlike hid, they don't raise leaf temp with infrared. Cool temps slow metabolism.
 

jimbonorman

Well-Known Member
I hadn't heard of that 4-8-4 so I looked it up. It's 2% magnesium already. They don't mention calcium on the label, but the first ingredient is fish bone meal, so it's definitely got calcium from that. I would say supplemental cal mag is probably unnecessary.

Ugh, so annoying when they don't put the full nutrient analysis on the label. I can understand not putting all the micronutrients but they could at least put calcium, magnesium, and sulfur...

Depending on how much you added to your initial mix, your top-dressing rates don't seem out of line with the manufacturer recommendations (I usually go with the "vegetable and herb" rate if they specify).
Based on that Mulder chart, it seems possible that I’ve overdone it with the Calcium and Magnesium and incited a greater demand/deficiency in Phosphorous. I’m actually noticing some subtle rust spots on the Dougs Varin now as well so I’m going to cut the Cal/Mag out for a few weeks and see what happens.
 
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