Author Topic: How to make potting soil more acidic  (Read 1797 times)

dunnyd

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How to make potting soil more acidic
« on: June 06, 2019, 04:04:09 PM »
Hi, so i ended up testing my blueberry plants soil (in a 24 inch width , 28 inch deep container) and the PH was 6..
I realize i probably should have done this before planting my plants.. but now that my plants are planted and established..how can i lower the PH? I used a 50/50 mix of organic potting soil + Peat moss .. but yeah the PH seems too high still.. do i need to repot? or can i add some sort of liquid to lower the ph?

Triloba Tracker

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Re: How to make potting soil more acidic
« Reply #1 on: June 06, 2019, 04:33:30 PM »
you can water with an acidic solution. You can dilute sulfuric acid, purchase "pH Down" which is used in hydroponics (just concentrated acids), or you could use vinegar.

Get some of the pH testing drops so you can test the pH of the water before using.

That's what I'd do in your situation.

If the plants were in the ground, you could still water with acidic water but you could also use elemental sulfur around the plant/tilled into the top of the soil. It slowly brings down the soil pH but may not keep it there without repeated applications.

shiro

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Re: How to make potting soil more acidic
« Reply #2 on: June 06, 2019, 05:53:01 PM »
If the plants are in pots then repoted seems easier to me, if the plants are in the ground there it is more complicated.
In any case it is important to check the PH of the water if you use that of the city, the rain water is generally neutral or acid so it is the best.

If your soil to a limestone nature the repotting is really important.
If it is a potting soil then the problem come may be rather water .
« Last Edit: June 06, 2019, 05:56:17 PM by shiro »

SeaWalnut

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Re: How to make potting soil more acidic
« Reply #3 on: June 06, 2019, 06:45:24 PM »
50/50 soil/peat moss mix its whats recomended for blueberryes.Use rain water and if the plant is growing well then dont change anything.What ph test did you used?

brian

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Re: How to make potting soil more acidic
« Reply #4 on: June 07, 2019, 10:12:17 AM »
I use "garden sulphur" which I believe is just granules of elemental sulphur that are slowly broken down by soil bacteria in containers.

Laaz

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Re: How to make potting soil more acidic
« Reply #5 on: June 09, 2019, 08:49:07 AM »
When I plant blueberries I dig the hole out oversize & back fill with a bunch of pine bark. then plant into that. Learned that from a old timer down here & it works well for me.

Patanax

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Re: How to make potting soil more acidic
« Reply #6 on: July 03, 2019, 04:59:52 PM »
Second vote for pine bark/pine needles:

https://youtu.be/i_xCSLU6e1o?t=528

Triloba Tracker

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Re: How to make potting soil more acidic
« Reply #7 on: July 03, 2019, 05:14:22 PM »
This is one of those unending controversies I guess.

If you google “do pine needles lower pH” you’ll see possibly more links about this being scientifically debunked than you’ll find people swearing it’s true.

Patanax

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Re: How to make potting soil more acidic
« Reply #8 on: July 03, 2019, 05:56:12 PM »
This is one of those unending controversies I guess.

If you google “do pine needles lower pH” you’ll see possibly more links about this being scientifically debunked than you’ll find people swearing it’s true.

Very interesting, I just looked it up. Thanks for the info!

I also found this overview by the RHS about acidifying materials: https://www.rhs.org.uk/advice/profile?PID=82