Natural Topdress to Lower pH?

DuskrayTroubador

Well-known member
Hey everyone,

I went out with my new, handy dandy pH meter the other day and the holes I sampled were all a little high on the pH scale, between 6.9 and 7.1.

Will a ph of 7 or 7.1 fuck things up?

If so, is there a natural topdress I could use to lower the pH slightly that would work in 4-6 weeks?

This is soil, of course, but I also have been trying to go to no-till, which is why I would prefer to topdress instead of digging shit up and mixing it it all again.

What do you guys think?

Thanks
 
Im not sure if that PH will fuck up things, I rarerly play with the PH to be honest.

What I do know is that other gardeners I have worked with use peat for this reason. How fast it will react I dont know.
 

Bud Green

I dig dirt
Duskray: Working outdoors with holes in the ground, that pH level shouldn't hurt you at all..

You could sprinkle used, dried coffee grounds as a top dress.. don't spread 'em too thick or it will form a cake...sprinkle 'em and scratch 'em into the top inch of soil...
They will add a bit of acidity to your soil...Plus, the earthworms love to eat 'em...

I deal with opposite pH where I am , so I sprinkle wood ash to add alkalinity and calcium to my holes...
 

OldSSSCGuy

Member
I'm like Veggie Farmer - stopped chasing pH after one really bad crop. Now I just ignore out and let the plants adapt. I remain convinced that cannabis is just a weed and it will grow in the most abnormal conditions - as long as they are consistent.
 

stashpot

Member
don't change it.. 7 is perfect for notill or orangics if you want to slightly lower it by .5 here and there use dolomite
 

40degsouth

Well-known member
Hi everyone, l hope you’re all well.
Duskray, a ph of 7 is widely regarded as the “perfect” ph not just because it’s neutral but more so because all elements are available. This is a great outcome for a “no till” gardener.
It’s much easier to raise and lock in soil ph than it is to lower it and achieve the same outcome. 6.5 is what l aim for and to achieve this l use large amounts of gypsum, that although being a calcium source (i.e. lime) will slightly lower ph because it also contains significant amounts of sulphur. I also top-dress with elemental sulphur at one handful per 300 gallons once a year, or once every two years, depending on gypsum applications, at the end of the growing season.
lt takes about a year for the sulphur to work because it’s actually bacteria that eat the sulphur that convert it into sulphuric acid, which then in turn effects the ph, there’s no quick fix and the soil will always want to return to its original ph as the acid is being neutralised by things like calcium and magnesium which is becoming plant available through the process.
As far as a top dress the only thing l can really think of is a clay slurry poured on, the reason being that most clay soils are acidic. Unfinished composts are also acidic but they are powered by nitrogen, so not recommended.
You can of course alter the ph of your (liquid) feedings by using organic acids like vinegar. I remember Tom Hill recommending to ph down to 5.5 for this in the “Growing Large Plants Outdoors” thread. Microbeman also dropped some really important information over at the “Local Materials” thread about using citric acid to ph down feedings.
Cheers,
40.
 
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St. Phatty

Well-known member
Fox Farm Ocean Forest ... cow manure ... any manure.

They all tend to run acidic. At least the run off does.
 

stashpot

Member
When growing in organics soil it's a natural ph buffer but only above 7.

So what happens is if you ph at 6 or below 6.5 the soil has a hard time buffering it back upwards.
when you ph it at 7 or above like 7 to 7.3 you give the soil a chance to buffer itself back to 7 or whatever the plant feels is best.. it tells you, you don't tell it.

for me i like around 6.5 to 7 sometimes i will go over 7 rarely and rarely go below 6.3.

But if i was you, you can also get organic ph down these days its literally lemon and vinegar etc its not harmful 1ml per 10ltr will lower a 8.5 to a 7 hope this helps.
Nice info from 40degs
 

DuskrayTroubador

Well-known member
Awesome, thanks for the quick, super helpful replies, guys!

Great to know that it's really not something I need to worry about. Also good to know that at a neutral pH the soil/plant essentially have the ability to self-regulate.
 
Came to think a little. Adding manure and urine and such, creates and chemistry effect that tends to be nn the acid side... But compost, generally end up between PH-7 and easilly uptill PH-8.

Its not rare for me to grow with compost from 50% and up to 100% if Im lazy, its winter or Im out of other soil ammenments.

My water is PH 7,45- PH-7,9, PPM 260/270.

This mix between this water with Calcium and compost mix thats probably high in PH aswell, I might do a home test, have grown fine fine plants. I should add some more Mg permanent, and sometimes a little K. Hmm.
 

OldSSSCGuy

Member
Look to dolomite lime as a light top dressing... And never use water which has been through a hot water heater; the lime deposits will make you chase your tail.
 

Three Berries

Well-known member
Came to think a little. Adding manure and urine and such, creates and chemistry effect that tends to be nn the acid side... But compost, generally end up between PH-7 and easilly uptill PH-8.

Its not rare for me to grow with compost from 50% and up to 100% if Im lazy, its winter or Im out of other soil ammenments.

My water is PH 7,45- PH-7,9, PPM 260/270.

This mix between this water with Calcium and compost mix thats probably high in PH aswell, I might do a home test, have grown fine fine plants. I should add some more Mg permanent, and sometimes a little K. Hmm.

Here is a good organic topdressing that does not affect pH greatly but does add some needed Mg, S and K.

LANGBEINITE - Sulfate of Potash Magnesia (K-MAG) Organic Fertilizer 0-0-22
 

Creeperpark

Well-known member
The original question answer is always to use peat moss to lower pH in outdoor soil. Peat moss 4.4 pH will lower high soil pH 7s and 8 down to the 6.5 range. It's good for only one 6 month season so timing is important. 😎
 
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