Soil Buffering

[Green n' Peace]

Thanks steelrat, i was thinking of going for PM light mix soil as a guy i knew said he never had problems with the PH in that soil either, be nice to choose from hard/soft water versions too as my water is hard water! I don't even know the difference lol! But i like to try stick with the same brand otherwise u just cant keep up if u get me! All im doing now is flushing my soil because i am having problems with the big SD, so not sure if the soil is locking out all the nutrients because i was feeding her ok and she seemed to be getting burnt on the tips/showing def's so must be a soil problem i stuck a probe in and the soil PH is over 7, so gunna do that then add some Epsom salts i guess to try fix the problem.

Hey, got the same prob in all mix last time i used it, Top of the plant was with tip burn and the bottom of the plant was yellowing very hard i dont know why that happened, the Ph was correct..

 

[blue]

i w

as feeding her ok and she seemed to be getting burnt on the tips/

Sounds like the symptoms of overfeeding KK!

 

[Green n' Peace]

So Blue, do you think plants can show signs of defs along with nute burn in some leafs caused by overfeeding?

 

[blue]

Hey GnP

I can't see any pictures, so my best guess would only be a guess.

But here it is.
My guess is that the PH was wrong for a while a nutes got "locked out" (as in not taken by the plant but still there in the soil)

.. Then perhaps the PH got put back into the right range and the plant went "oh good - theres tons of food here for me to eat" ... and wallop - burned.

The defs potentially would have shown up before the tip burn.

It's only my best guess - but 9 out of ten times - it's a PH problem.

 

[KannibisKing]

i w
Sounds like the symptoms of overfeeding KK!

i dont think thats the case though here blue! she is showing def's hard, not sure whats wrong

 

[Dr Who]

If the pH has changed (it's the pH in the soil that's important, rather than the pH in the water) from ideal to elsewhere then you could have a deficiency of one nutrient whilst at the same time you have high availability of another (which might be present in excess). Have a look at the change in availability of different nutrients with pH. It might (but might not) help if you think you have deficiencies and excess (of different nutrients) in the same plant.

John Innes composts are also pH balanced, but not organic as far as I am aware.

 

[Green n' Peace]

You are a sent of god, never thought about it this way, but makes so much sense that i feel so idiot right now. Thanks Blue

 

[blue]

I've been puzzling over your picture in the help thread for a while!

I don't advise on deficiencies because i'm not comfortable at giving you the right info.
here's the sheet that i spend hours gazing at.

It mostly makes me more confused

..Most likely (in my humble opinion) N def progression or late. (but zinc's looking tasty too hehe - see?! I just don't know!)
:Sharing One:

 

[Muddy]

I would not recommend aluminium because under the wrong conditions (low pH) this might be quite toxic to the plants and could inhibit root growth. It seems likely that you could get this situation if you are trying to lower pH.

Aluminum sulfate is not toxic to plants, at least not at the levels needed to bring the pH of most commercial soils into the proper range. In fact, it is a staple in the commercial nursery business to lower soil pH for acid loving plants. If the starting soil pH is 7, 4 grams of 17% AS per gallon of mix will lower it to the 6.3 - 6.4 range. I've personally tested AS for over a year now over a range of auto strains. I see no reduction in the size of my roots, the size of my plants or in my yields.

The pH of rainwater is (in principle) about 5.65.

The pH of rain water will vary from location to location and from one rain fall to the next. Mine is always alkaline, ranging from a low of about 7.2 to a high of 9. Generalized statements like this can be misleading and confusing, especially to new growers who are still learning.

 

[KannibisKing]

Looking at that pic blue it looks like I've got early and late stages of potassium def. after this flush I will try bump up the flower nutes a bit, and get some aluminium sulphate should sort things! Thanks for all your help guys. So PHing my water lower isn't going to effect my soil instantly right?