I checked my potting soil pH .. its 7.6 :(

[ScienceSeeker]

I just got very nice potting soil from friend because his flower garden has so many flowers that one cant even see the leaves .. He happily gave me a bucket full of his potting mix. ( He does not know that I will be doing cannabis in it ! )

Now, before I plant cannabis in this potting soil, I pHed it and it comes to 7.6 , I know that cannabis in soil needs 6.5 ... so .. .. I am sad .. I want this soil to be pH 6.5 .. how to do it ? .. can such be done? ..

I know club soda is CO2 dissolved in water, thats weak carbonic acid .. right? should I just wet this sand using club soda? will it work ? .. I dont want to return this soil .. it smells heavenly earthy.

I want pH of this sweet sweet soil to be 6.5 please.. thanks... if it works, I am going to plant Gorilla Girl in it from Sweet Seeds .. yum yum yum

Thanks a loads.

 

[Rev. Green Genes]

Thats a pretty easy one. You have a bunch of options. The "proper" nurseryman would tell you to add a sulfur or aluminum. I recommend sulfur of those two, and it is a permanent fix. Most people use pH down, it comes in a liquid form and you mix it with water and add to the plants. There is a third method, but it is not permanent. That is to use vinegar (acetic acid) mixed with water.

There are also fertilizers for hydrangeas and rhododendrons that contain acidifiers, and that can work too. Using sulfur can take a week or two, but is the best and most permanent solution.

 

[ScienceSeeker]

Heh, thats cool, I have white vinegar right now, I will have to buy sulfur ... how frequently vinegar is needed? If its going to be as simple as adding some to the water, thats no biggie .. I can do that.. tell me more about using vinegar to fix this soil please.
thanks

 

[STILLSMOKIN]

I've seen people do a ph bath for soil. The only problem with soil is canna likes a nice fluffy medium. If it were me and I knew it was good stuff, is cut soil with coco, perlite, and seed starter in middle to be easy on the new babies. Then just ph water to feed and medium will drop in time for flower when ph matters most

 

[GoAuto6]

If your staying organic all the way through, you do not need to pH it.

 

[Waira]

mate, first and foremost is that reading needs to be verified as accurate- ...how exactly did you take it? If you have a good, calibrated pH meter, you have the luxury of testing that soil doing a slurry test,... take a 1/2 cup of moist soil, add about2/3 cup of RO/Di water (low ppm is important here), mix and let sit for hald an hour,.. drain off the liquid and test it.... You can get soil pH meters too, down the road here,.. the Accurate 8 is a decent unit (love mine!), not too $$, or get one of the more $$ ones like the Blue Lab's version.. this is basically a modified pH meter, and as such requires the same, even more care as a pH meter because of it's rougher duty, so note that... don't use your pH meter for in-pot measurements in any case.... :smoking:
Once that's figure, we can recommend how to get it lower and stable there,... Ask you friend how rich it is, is it safe for seedlings....

 

[ScienceSeeker]

Thanks for all replies.
Asked him, he said exactly what was advised above .. that do nothing about the pH, he said that its tested for slurry 6.8 pH and he said that soil has a healthy mix of 20% vermi-compost 20% washed cocopeat .. rest is soil .. and then he used some buffer solution to 'caliber' my digital pH meter.. which now shows nearby reading. So safe to say as everyone has suggested .. safe to use this soil and start my grow ?

 

[Waira]

:smoking: yes....

 

[The Fish]

My meter went bad so I mistakenly added lime to adjust my ph up. Now I'm on the high end with this grow, so I add a tbsp white vinegar every feed and the girls love me for it.