Soil PH

 
Hi,

Just a quick one.
I know how to increase the soils PH. But what do i add to bring i
down.
Thanks Mar


--
CORVIDSTATION61

 

Add pine or fir needles, or add elemental sulfur powder.
--

Billy

Bush & Cheney, Behind Bars
http://www.gallup.com/poll/102577/Half-Strongly-
Disapprove-Bush-Job-Performance.aspx

 On 2007-12-22 16:55:40 -0500, CORVIDSTATION61


Go to the garden center for sulfate.

 

Hi Mark,

There are several right ways and one wrong way.  

Do not use Aluminum Sulfate.  The aluminum builds up in the soil and is
toxic to many plants including rhododendrons and azaleas.  There is one
exception.  Aluminum Sulfate will normally make blue/pink hydrangeas
bloom blue since they require both aluminum and acidity to bloom blue.

The right ways include:

Ferric Sulfate
Flowers of Sulfur (powdered sulfur)

If the soil is too alkaline, acidity may be increased by adding flowers
of sulfur (powdered sulfur) or iron sulfate. I add 1 tablespoon of
sulfur powder around the base of any plant showing signs of chlorosis.
Around established rhododendrons and azaleas, do not disturb the shallow
roots. Sprinkle the sulfur under the mulch and then replace the mulch.
Do not use aluminum sulfate. Aluminum can build up in the soil to toxic
levels eventually. One very common source of chlorosis is when lime
leaches out of concrete, such as from a foundation or walkway, making
the nearby soil more alkaline. This problem decreases each year as the
concrete ages. An annual application of sulfur can compensate for this
problem.

For table on how much elemental sulfur is needed to lower soil pH, visit:

http://rhodyman.net/rarhodyho.html

 and click on "Soil pH"

--
Pardon my spam deterrent; send email to rhodyman@earthlink.net
Cheers, Steve Henning in Reading, PA USA - http://rhodyman.net

 On 12/22/2007 1:55 PM, CORVIDSTATION61 wrote:

Besides sulfur and iron sulfate, use nutrients (including fertilizers)
that are acidic.  For nitrogen, I use ammonium sulfate, being careful
not to use a lot all at once because it can burn both foliage and roots.
 I dose my roses with Epsom salts (magnesium sulfate) because the
magnesium promotes the growth of new "canes".  My citrus and gardenia
get a small amount of zinc sulfate added to the fertilizer whenever I
feed them because they need more zinc than most other plants.

Gypsum (calcium sulfate) is very slightly acidic.  I use large
quantities to break up my clay soil, but that's still not enough to have
any significant impact on soil pH.

Sulfur and the sulfates acidify the soil through the action of soil
bacteria that slowly convert sulfur into sulfuric acid.  Be careful that
you don't overwhelm these bacteria with too much sulfur and fertilizer
all at once.

Elemental sulfur does not readily dissolve and remains on the surface.
Thus, you must create an environment where the acidifying bacteria are
also on the surface.  It helps to keep a light mulch of compost or
decomposing leaves.  On the other hand, most sulfates do dissolve quite
easily.  (Compost itself tends to be acidic as is peat moss.  My compost
is mostly leaf mold, which is even more acidic than normal compost.)

Where the soils or water are naturally alkaline, acidifying is a
constant effort.  The sulfuric acid is quickly neutralized; what is left
leaches through the soil beyond where it will have any benefit.  I
broadcast sulfur around selected plants every year.

NO!  Do not add sulfuric acid to your soil.  You will kill everything.
Let sulfuric acid be formed gradually by natural processes.

--
David E. Ross
Climate:  California Mediterranean
Sunset Zone: 21 -- interior Santa Monica Mountains with some ocean
influence (USDA 10a, very close to Sunset Zone 19)
Gardening pages at <http://www.rossde.com/garden/>