I'd like to know alternative acidification methods other than peat moss, which damages the environment through it being harvested.

I know a lot of people will tell us how wonderful peat moss is to acidify soils, but I'd like to know what else is available, for those of us that feel peat moss harvesting is damaging to our environment. Hopefully this'll help out the OP'er as well as myself..

Pine needles for mulch.

Lorna

Other than peat, elemental sulfur is an approved organic soil acidifier. Cottonseed meal will have a similar effect but it requires more to achieve an equal level so may be expensive if attempting to alter a large area. Watering with a mildly acidic solution of 1 part household vinegar to 10 parts water can also help.

Mulching with pine straw or oak leaves or similar so-called "acidic" mulch will have a small effect on pH but only at the soil surface. If these material are incorporated into the soil, they rapidly lose any acidifying properties once decompostion begins.

Most soils have a buffering capacity that resists substantial changes in pH - any attempt at significant change will be temporary at best and will need to be repeated frequently to maintain the desired level. If you are attempting to alter soil pH by more than one point on the pH scale (a tenfold decrease or increase), you are probably better off growing the plant in a container, where soil chemisty can be more closely regulated.

Contrary to long held belief peat moss, pine needles, Oak Leaves etc. do not change a soils pH enough to be of use for that purpose. Although they all will test as having a low pH so will maple, beech, birch, and all the other tree leaves.
Cottonseed meal has been suggested for use as an accetable organic material for many years, but most all cotton grown today is Genetically Engineered to be resistant to glyphosates and is one of the most sprayed, with pesticides, plants on the planet. We should be seriously rethinking the use of cottonseed meal, at least by organically minded people.
Elemental sulfur is about the only thing that is currently available and accetable. The research I've seen indicates it would take extremely large volumes of vinegar to change a soils pH and that would kill all plant growth in the process.

Why are soils which blueberries are found in naturally acidic? I've always wondered that

Couple of things that need addressing. First, GM cotton is not modified to be resistant to RoundUp (that's soybeans) but has had genes added that make it more resistant to insect issues - the same reason non-organic growing operations use pesticides so heavily on cotton. If not genetically engineered (and there's still lots of non-GM cotton being grown), the meal made from ground-up seeds contains only trace amounts of pesticides and these meals can be/are composted to eliminate even those trace amounts and ARE organically approved. There is also a huge sustainable organic cotton movement and all by-products from this are considered fully organic. One can find organically certified cottonseed meal available through various sources - just look for the NOSB certification. It's not inexpensive but it will do the job of acidfying soil pH and much faster than elemental sulfur. If you are amending for specific plants and not a large area, this may be the way to go if peat is not your choice. And FWIW, peat is still considered an excellent and organic soil acidifyer but for personal reasons is not everyone's choice.

Routine watering of acid-loving plants with a dilute vinegar solution (or lemon water - give your plants lemonade!!) will help to maintain an acidic soil pH but works best with containerized plants. One is not attempting to significantly alter pH with this method, only to assist in maintaining it against natural buffering effects. Concentrated acetic acid (20-25% vinegar - 'Burn-Out', 'Blackberry and Brush Blocker') is used as an organic herbicide and will radically alter - at least temporarily - soil pH but this is not what is being recommended here. Dilute vinegar water is widely used by bonsai enthusiasts as well as other less conventional "herb" growers. Simply put, it works.

What about greensand?

Greensand (glauconite) has no measurable effect on soil pH, which is a good thing as its pH tests out around 8.3 It is an iron potassium silicate often used to provide a slow release source of potassium and offset iron deficiencies in heavily alkaline soils. Because of its structure (a rounded clay pellet/grain)and high cation exchange capacity, it is sometimes recommended as a method (pretty expensive) of loosening and lightening clay soils.

Why are soils which blueberries are found in naturally acidic? I've always wondered that.

Much of the soil blueberries grow well in around here are peaty soils in the first place.

Up in Maine that isn't the case I don't think, as well as Massachusetts...it's rocky clay glacial leftovers..what..glacial till or something..not much organic matter at all.

Well, I found this about Maine soil. Does it help?

Here is a link that might be useful: blueberries and granite

Whether a soil is acidic or alkaline depends on many factors and one of them we know about today is rainfall. Areas of the world that have ample rainfall tend to have soils that are more acidic while those areas of the world with less than ample rainffall tend to have soil that are more alkaline, because the tinigs that cause a soil to be alkaline do not get rinsed out of the soil. So soils east of the Mississippi tend to be more acidic than soils west of the river, because of the average rainfall and that is where blueberries naturally grow.
And cotton is Genetically Engineered to be resistant to the glyphosate products because that is the herbicide most often used on cotton fields, as is Corn, the Soybeans, and now some of the wheat, and the "weeds" are getting those genes and becoming resistant to the glyphosate products.

Kim,

You're totally wrong. It starts at Trinity river in Texas. East of that is acidic (East Texas) and west of it tend to be alkaline soil. Easy to grow azaleas...

My azalea bed sits on top of limestone and I never used peat moss. I use quite a bit of greensand, lava sand and a lot of mulching...

Plant in the spagnum moss, ammend with sulfur/iron, add plenty of organic matter and mulching with pine needles. Be sure of good soil moisture and adequate drainage for a healthy growing environment.

I too, have come to believe that little can be done to change the ph of soil in general. But adding these acidifiers seems to do the trick if everything else is as it should be.

Lou, the USDA Soil Conservation Service, most all of the soil scientists that I have talked with, the USDA Natural Resources Conservation Service will all tell you that as a general rule soils west of the Mississippi will tend to be alkaline because of the normal lack of adequate rainfall. There may well be exceptions to that rule, exceptions to that rule that will appear on the Soil Conservation Services maps. East of the Mississippi you can find soils that are naturally alkaline, too, which does not change the fact that as a general rule soils east of the Mississippi tend to be acidic, because the more than adequate rainfall.
Azaleas and Rhododendrons grow quite well around the cliffs of Dover in England, limestone, why?

Kimmsr, please explain the use of garden sulphur to me. Five years ago I bought a container of something I was told was natural sulphur. I was told it would be a real boon to both flowering and produce plants, and a necessary acidifier to my desert soil. I dug it in, according to directions. Two and three years later as I dug soil for spring planting, I found many traces of the yellow sulphur.
I had expected it to decompose and integrate into the soil. By the way, I didn't notice that it had any good affect on my plants. I use well water which has sulphur, so is it prudent to add powdered sulphur? Thanks, in advance, for your consideration.

Lorna

just piping in real quick, would wood ash work to make soil more acidic, Im not sure but figured id through it out their and see what you all think

Fill a hose end sprayer with Humic acid, set the dial on 3 tablespoons per gallon and saturate the soil beneath acid loving plants about every two weeks. This treatment will slowly lower soil pH. After one growing season you can reduce applications to four times a year. Couple this with organic cottonseed type mulch products and you should have success with the acid lovers. Just a reminder for those trying to grow blueberries. The Sunshine Blue blueberry variety (grows in Zones 5-9) thrives in higher pH soils. Although it only grows to a height of about 4' it produces a heavy crop of tasty, medium sized fruit.

Wood ash makes soil more alkaline.

Lorna

thanks for straightening me out Lorna, I knew it did something how bout baking soda ??? or is that the same effect, or just a crazy idea

Lorna;
Whether, and how soon, sulfur may change your soils pH depends on which sulfur you used and how much was needed to make the change necessary. Wettable sulfur has been treated to make it more easily disolved in water because sulfur normally does not disolve in water.
How much sulfur was used?
How much sulfur was needed?
What kind of sulfur was used?

I don't remember what type it was Kimmsr, except that it was a yellow powder, which I used according to the directions on the label. Is sulphur in one's water negligible? Soemtimes I can smell sulphur in my well water, but most of the time I cannot.

Tn jed, I'm sorry I have no idea what baking soda might do to soil. I've used it in a spray to get rid of powdery mildew on plants. Otherwise I haven't used baking soda in the garden. Anybody else have any knowledge about this?

Lorna

Lorna

Baking soda is sodium bicarbonate and is a base (pH~9.0). Adding it your soil would make it more alkaline but you would likely have to add considerable quantities to get much of an effect. OTOH, it is also a salt and this would probably create more of an issue with plant health than whatever increase in pH it might accomplish.

3 TBS elemental sulphur per blueberry plant is what I have used since originally posting this question. Of course, it rained 11.5 inches in 3 days here so it's either well waterd in or washed out.

There was mention of using vinegar to help maintain Ph levels against the natural buffers in the soil.
Is there any use of leftover coffee? Would it hurt to pour onto house plants or even outside? For blueberries, strawberries etc.?
I had read, in FAQ, that the acid is typically leached out of the grounds during brewing so it is evidently in the drink.

I use apple cider vineger in my drip irrigation from time to time to clean out the calcium deposits. It is diluted at a rate of 1 tbsp per gallon of water and this not only provides a good cleaning of the emitters, it creates a nice response in my tomato plants.

As for permanant PH changes. I think adding organic matter will help return any soil towards neutral. That and planting plants that are adapted to your area are the ideal. For plants that are not adapted to the local soils, containers with an appropriate container mix are the best bet. Trying to change native soil too dramatically is going to cost much more time effort and money than a container and mix.

Pine straw is a good mulch for any plant & a tiny change in pH, because of pine straw is good.Sulfur is better.WHY does Rhododendrons grow on limestone.
The people in the know have been saying that Rhod. does not need low pH, but tolerates it. That the plant needs magnesium sulfate(Epsom salts). I know a 94 year young Nurseryman that put Epsom salt in his pine bark/sand potting soil 40 years ago.

Ok. Wanting to make sure I heard this correctly. My soil was tested and I am too alkaline. My organic solution options are the following

1. Till in some peat moss
2. Water with some watered down vinegar with some frequency
3. Mulch with pine needles
4. Add Elemental Sulfur (is this really organic?)
5. Add coffee grounds to the soil

or a combination of the above

Was in London UK in april. There were amazing blueberries there: huge size (almost like the montmorency cherries) and strong delicious flavor, much much more flavorful than any I've had here on L.I. including those off the bush grown on Eastern Long Island. The box said Grown in Spain. How do they do it there???

Used coffee grounds are Ph neutral, its the coffee itself that is acidic. But just like adding vinegar, its only a temp fix. Unless you are using bags of used coffee grounds mulched into the soil or composted, used coffee will only have a temporary effect on Ph unless you do it all the time. Now if you do it on a constant basis it will lower the Ph of soil by adding OM to the soil and creating a healthy environment for earth worms:-) Ive been using the remains of my morning and daily coffee grounds (with some liquid coffee left) around my garden for about a year now. The spots I have been treating have become nice and black and the plants seem to be doing pretty good. I have only recently been adding around my citrus.

To begin to lower the Ph of my soil around acid loving plants/trees this is what I did:

Removed any grass in an area 4'x4' around any Citrus tree

Laid down a general purpose 10-10-10 slow release granule fertilizer containing ammonium sulfate

On top of that I laid composted steer manure (Wish I had some finished compost to top this with)

On top of that I covered with pine bark nuggets

When I water I use apple cider vinegar to lower the Ph of my water to 6.3 (I know its only temporary but it helps I'll eventual get some Ph down product)

I use a 20-20-20 liquid fertilizer with micro's to foliage spray and feed around the tree at half strength every 2 weeks to 1 month during the growing season.

I also have some compost cooking and I cant wait until its ready to use:-)

I just recently began adding to my new plots for citrus the Epsoma Citrus Tone and Acidifier. We will see how that works.

I do know from the above that my soil in the past month has dropped almost more than .5 It was over 7.8 and now its at around 7.0-7.2. The rest of my soil around my yard is right around 8. And I think thats kinda high for what I grow.

Why would someone come to an Organic Gardening Forum and then talk about using synthtic materials to try and do something they will not do? 10-10-10 and 20-20-20 fertilizers are synthetic, unacceptable to anyone practicing organic gardening/farming.
Elemental sulfur is what to use to lower a soils pH, not Magnesium, Apple Cider Vinegar, or Vinegar, or much of anything else.

Blueberry Apple Cider Vinaigrette, yum

I have been an avid organic gardener for many years and for the past few years have been exploring the world of bokashi composting (pickling actually) and have found that the resulting fluid from the process provides a natural acidifier (mine tests between ph 3.5 and 4.5) that is rich in microbial life. This may only provide a short term change to soil PH. However, since I am continually making this, I have a fairly constant supply.

blazeagorly, is your foliage spray Organic & what is the brand name?

Refresh my memory, I havent been here in a while haha.

I do have a few sprays but lately I just let the natural predator bugs take over. Only problems I have are CLM (which I am slowly getting under control) and the damn ACP (which I just blast off with a hose and let lace wings and lady bugs eat them)

EDIT: Copper for non citrus only. Forgot this was a soil thread