Blueberries and Battery Acid Adventures

Eventually yes, it may take some time. And if you add sulfur you can negate the effect. Hard to get right.
@me2 and @cowardly_lying discussed a lot about the chemistry of it all better than I could. I hate chemistry and I love chemistry. I have a hard time remembering all of it unless I’m doing it on a regular basis. It really helped me though to read what they wrote to understand better what is going on.
Even though I think they overcomplicate it, it’s more of an opinion than fact. I was a smart ass about it, sorry about that.

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I’m curious what pH meter do the experts among you use. I have had difficulty growing blueberries, and have looked at online available meters from Amazon and other places. I have not been satisfied with their reviews in terms of reliability. So I am seeking advice about what device to purchase.

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I think most people here use the paper test strips
I mix soil and distilled water in a small Tupperware and dip a strip. Any accurate pH meter is over 200 dollars and require periodic calibration. I purchase the low end pH that only goes up to 6 because I only use it for blueberries.

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I measured the PH of my blueberry pots this morning at between 5.5 and 4.5. One of the plants has put on a ton of growth.

It seems like even if your soil is not very acidic, while you wait for the sulfur to lower your ph, if you irrigate with mildly acidic water your plants will be able to get the nutrition they need before the water is neutralized.

You can buy pure sulfuric acid drain cleaner from Walmart for $6 a quart. You have to check the ingredients. Most drain cleaner is not sulfuric acid.

I put on my safety glasses. Then I fill a 1 gallon water jug 3/4 full of water then add 1/4 cup of the drain cleaner into the water jug. I never play with the drain cleaner bottle without wearing the glasses. Then I wash my hands.

This makes a much safer diluted acid mixture. When I water the plants I just add a splash (1/8th cup?) of the diluted mixture into my 2 gallon watering can. I then measure the ph of the water with a cheap Chinese PH meter. I look for under ph6 and over ph4.

I am a total noob, so if anyone disagrees, chime in and let your wisdom shine.

I’m also convinced there are great variations between each blueberry type. I have a pink lemonade that has always done great but the blue crop and jersey seem to be extremely sensitive and almost always has red leaves. They are all in the same bed of 90% peat moss and 10% leaf mold.

I put in a reverse osmosis system last fall and i’ve been banking a gallon here and there for blueberries/other plants. I haven’t tested pH but hardness drops from about 320ppm to 25ppm.

Now i’ve read that RO water (pH of 7) if exposed to air lowers the pH to 5.5 or so because it is grabbing co2 from air…what kind of wizardry is that? …

Only issue with RO is its slow to recharge the holding tank and has a lot of filters to replace.

edit to add…thinking about it for a minute, i think my system (maybe all of them?) has a polishing filter that it goes thru last…that probably is adding some hardness back at the end//maybe changing pH some. I suppose one could remove that if you just need plant water///but we use it for drinking/cooking.

Thank you!!!

I grow pawpaws commercially. They thrive in acidic soils. My well water for irrigation is quite alkaline, so I must add sulfuric acid (battery acid) in my fertigation. I use a Dosatron to apply both a fertilizer and the acid. I’m adding about 13 ounces of acid in 250 gallons of well water. That works out to .052 ounces per gallon–not much, but it’s effective. I use test strips to confirm my water pH. I highly recommend a full laboratory test of your irrigation water to learn the alkalinity and pH. Then you can go to an online calculator to figure out how much acid you must add.

It’s also useful to do a pour-through test of your soil or container media. You will find instructions for this online as well, but it involves pouring distilled water through your media and measuring the outflow for pH.

And yes, be careful with the acid. I buy it by the 5-gallon bag in a box at NAPA. Remember your high school chemistry class: “Do as you aughtah…add acid to watah!” And wear gloves and glasses.

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Is there a way to tell between nutrient deficiency from pH and it just being too cold? I put my blueberries in about two weeks ago and they have all turned pretty red. I planted them in 60% peat moss, 20% sand, 10% top soil and 10% compost. Mulched the top and top dressed with some sulfur. My pH probe is measuring the soil about 5.5-6. It’s pretty pretty cold the last two weeks too though, mid 50s in the day and mid 30s at night.

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Yeah all of my blueberries are red from the cold. They are growing anyway. So that is a good indicator it is temps. Zone 6a here. As of today it’s going to be 70 during the day and 50 at night. They should start turning green soon.
@marc5 good info thanks for posting.
@warmwxrules interesting about the RO system.

OP here. Posting some follow up. All of my potted blueberry plants are doing great. All of them put on serious growth. Over the summer I did occasionally irrigate with a weak sulfuric acid water mixture. The water mixture had a ph of 4. I also used tap water often with a ph of 7.5.

Carefully using sulfuric acid drain cleaner mixed with water seems to make the blueberries happy.

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The TDS of my rain water reads 6-7. Should I be buffering with something before acidifying?

Should I be aiming for low 20s?

What should I use to buffer? My goal is to gravity drip irrigate from 275G tanks and yes I know it’s going to be challenging and variable.

If I was mixing something for immediate use, I would use organic fertilizer of some sort but don’t want nutrients sitting stagnant in tanks. I have some SeaAgri 90…?