How do I compensate for over-acidifying blueberry soil?
In my usual paranoid fashion, I overdid it in acidifying my blue berry container growing media. The university test came back at 3.8 Ph.
My response to this was to cease watering with water treated to Ph 5 by sulfuric acid and to instead water with city tap water. If anything, the plant did even worse.
I wised up thanks to you guys and started testing with narrow band (4-7) ph strips which correlate very well to university soil test results. The acidity of the media hasn’t improved one whit—-I assume that the long term effect of soil sulfur has outrun the effect of city tap water.
I’ve just about given up on the plant. Probably I’ll start over. Any other suggestions? Will the use of alkaline tap water mess up my plants even if the soil Ph is very low?
Well, as you’ve found out, moving soil pH up or down once the plants are in can be difficult. Without adding lime you’ve going to have fits trying to move it up, and liming is best done when you can till it all through the soil.
If the plants have gone dormant for the winter you could pull them out and adjust your soil then re-plant. You might not have much to lose, your bush is a goner as it is unless you can adjust the pH. You might want to plant varieties that are more tolerant of high pH in light of your tap water situation.
Water it with tap water till the water is running out and then water it even more, Flush the soil. I use tap water to balance things out all the time, it will not hurt the plant. You need to try and push some of the hydrogen ions right out and so you need to flush it extremely well. If plant dies well I killed two this way, so welcome to the club! Buy another, try again, but don’t give up just yet.
As applenut suggested would probably work better to move the plant out. Adding compost should raise pH. Yes with lime it may keep working for a year, and then you’re on the other side! It’s probably best to remove plant, start with new soil. In containers when you use a mix of peat and pine bark the pH stays about 5.0 as that is the pH of both pine and peat. So no sulfur, If you use Holly-Tone you’re adding sulfur, you can counter with watering a few times with tap. Urea is only slightly acidic and will not lower pH like Ammonium sulfate does.
Miracle grow for acid loving plants is easily available urea for blueberries. Blueberries like urea too.
There was probably some damage done and necrosis was being seen,even though the higher pH water was added,as the plant was gradually dying.
I’m not sure if sudden higher(or lower) pH change will hurt a plant rather than a gradual difference.That’s an interesting question and a possible experiment.bb
Yes, I wouldn’t expect high acid to cause instant death at all, although I’ve no experience over-acidifying container soil. I should think Drew’s method would likely work but if it is as lethal as suggested, I would have taken the plant out of the pot and put it into a tub of water letting the soil wash away and then carefully repot it. Dormant or not- that shouldn’t kill it or even be that much a set-back. Most roots would be saved that way.
I mixed my over-acidified container soil half and half with some compost that tests at around 6.75 Ph and it was still off the scale acidic.
So I’ll start over, sort of. My container mix consists of sifted compost, Diatomaceous earth and peat moss. I’ll get a mix that tests around 5+ Ph, replace the top half of my container (I use extra large 20 gallon containers) and apply Osmocote based upon an old post by Fruitnut. I propose to use a weak solution of Urea mixed with water acidified to rainwateresque Ph instead of ammonium sulfate as Fruitnut advocates.
I figure that by the time the roots hit the lower boundary, the water will have equalized things as suggested earlier in this thread.
I ordered an extra new plant and I’ll use the necrotic one for experimentation.
Yes, seen that. I reused my soil, it didn’t take much to readjust. About 10 gallons of tap through it and it was basic. But that would depend on the amount of carbonates in your tap water, not just the pH of the water.