Soil Ph & Nutrient Uptake

[jumpincactus]

Here's a graph I found today while looking for data on soil acidity and liming.

What Ph levels do you use in your soil grows???

See link below for full write.

Table 1. Plant Nutrient Recovery as Affected by Soil Acidity
Nutrient Recovery (%)

Soil pH Nitrogen Phosphate Potash
7.0 70 30 60
6.0 63 15 60
5.5 52 15 45
5.0 38 10 30
4.5 21 8 21

http://www.shsu.edu/~agr_www/documents/SoilAcidityandLiming.pdf

 

[Seamaiden]

I shoot for a range of 6.2-6.8, specifically for soil.

 

[Toaster79]

That's soil pH right?

I shoot for a range of 6.2-6.8, specifically for soil.

 

[Seamaiden]

Yup! Hydro (including perlite-only) would be in the low-to-mid 5's, and for me for coir growing the best advice I got was to keep it between 5.8-6.2 (thank you, dcyans, wherever you are), with 6.0 generally being the sweet spot for the *vast* majority of strains. I haven't done undercurrent, expanded clay, Pro-Mix or peat grows yet, so I can't speak to the best parameters for those methods.

 

[Toaster79]

Thanks Sea! You're a real sweethart :)

I'm asking 'cause i did slurry test today with my tap water at 7.4 pH and my pH meter showed 6.7 when i mixed 1 part soil and 1 part tap water. So does that mean that my soil pH is 6.0?

Keep it green!

 

[Seamaiden]

Thanks Sea! You're a real sweethart :)

I'm asking 'cause i did slurry test today with my tap water at 7.4 pH and my pH meter showed 6.7 when i mixed 1 part soil and 1 part tap water. So does that mean that my soil pH is 6.0?

Keep it green!

Yes, assuming you let the mixture sit for a long enough period of time. I have found that nothing changes after 7 minutes, so that's my mark. :)

 

[Toaster79]

PH has conductivey it is always changing.. Water to waste 30% every time you water, You should always get back what your putting in!!!! Measure your run off...Have you ever measured your run off? If you don,t run to waste 30+% your ph is 4-8...5-2 max!!!!and your TDS is over 3000 Just cheek it..& fix it...

Im in soil! Why would I feed with 30% run off and drown my plants? There's nothing to fix. I was just asking out of curiosity.

Yes, assuming you let the mixture sit for a long enough period of time. I have found that nothing changes after 7 minutes, so that's my mark. :)

Thanks! That's how long it usually takes with my pH pen to take accurate measuring.

Keep it green!

 

[Toaster79]

If you say so.

No, I never measured my run off 'cause I never needed to and never had any. I never measured EC either 'cause I don't see the point of measuring green compost or EWC teas EC. Why are you so sure my soil is too 'heavy'? You heave no idea what soil or mix I'm using, you have no idea what is my watering/feeding regiment, have no know abouts what nutrients if any I'm using and you're still throwing your numbers in my face like those are some facts. Bold move there mate. But keep it up! You're the pro.

Keep it green!

 

[Seamaiden]

I've done some cleaning up of this thread. People who can't play nice are going to have to play somewhere else. PERIOD!

 

[Seamaiden]

If you say so.

No, I never measured my run off 'cause I never needed to and never had any. I never measured EC either 'cause I don't see the point of measuring green compost or EWC teas EC. Why are you so sure my soil is too 'heavy'? You heave no idea what soil or mix I'm using, you have no idea what is my watering/feeding regiment, have no know abouts what nutrients if any I'm using and you're still throwing your numbers in my face like those are some facts. Bold move there mate. But keep it up! You're the pro.

Keep it green!

I find measuring run-off to be a poor method for me for figuring out problems. Also, I feed much like you do, using organics whose EC cannot easily (let alone accurately) be measured. I far prefer a slurry test, as we've been discussing I believe. DISCUSSING. :) Thank you for keeping it nice here.

 

[hotrrod7076]

Cool yea im here to learn n anything i can add i will n i greatly apriciate all the info the local grow shops around here everyone has there own ideas n kinda stopped listening to a few of them when i was told i have to many luminums in my flower room n how i shouldnt do this or that ...when the my final buds beens coming out fantastic far as density and resins n trichomes ..which i did all the math n my flower room is about 9200 luminums per sqaure foot which im trying to mimic the suns out put n they say it 10,000 luminums per sq ft n the few questions i had on here u guys been way more helpful on things i tried coming from u all :-)