Who tested the soil and what were the results? It looks to me like water stress coupled with too high a ph. Where are you located?

How long have you had these plants and what kind of water do you use and how often are you watering? Reason I ask is cause in Houston we have been in the worst drought on record but Ive been watering daily if the temps are above 90 degrees and Im not showing any signs of drought stress. Could be your watering schedual and like Bamboo said too high PH

I water the plants every day with acidified water (sulfuric acid) and the Ph is about 5.5
The plants with the reddish leaves have no drought stress.
The soil test shows PPM - 47N 62P 212K 1.9Cu 102Mn 140Fe 5.7Zn 6400Ca 590Mg
I saw that the Nitrogen was on the low side so since then I added some Ammonium sulfate.

What have you been fertilizing them with? Did it have muriate of potash in it by chance?

Your blueberry leaves do not show the signs of high pH that I have seen in our shrubs, here in Madison, Wisconsin. Possibly the pH is too low, or these shrubs are suffering from excessive nutrient, maybe too much fertilizer. That is just a guess. What method are you using to measure pH? In particular, how are you measuring the pH of the acidified water that you are using on these shrubs?

I have used Potassium sulfate, Phosphoric acid, Ammonium sulfate, Magnesium sulfate. Ph is 5.5 or may be slightly higher and I measure it with Ph meter

Penandpike,

Have you checked to see if the PH meter is reading accurately?

Lawn & Garden centers sell metal probe type pH meters that cannot be calibrated using a standard solution of known pH. Conventional pH meters, used in laboratories, & also in the field, have a permeable glass bulb, located at the tip, & there will generally be a battery power supply. These must be calibrated before use, using two solutions of known pH, that bracket the range of expected pH. When checking soil samples from our blueberry shrubs, I use two calibration solutions, one at pH = 3.5, and the second solution at pH = 7.6. For several years, I have been using bromocresol green dye indicator solution to check soil pH. This indicator covers the range 3.8 to 5.4, which is a narrow range, but appropriate for blueberry shrubs. One advantage to using dye indicators for checking pH is that no calibration is required. I can tell you, with confidence, from many years of experience testing pH, that results from using a calibrated pH meter agree with results from testing with dye indicators, and that these results are confirmed by the appearance of blueberry leaves, which are deep green during the growing season, when pH is in the range 4.5 to 6.5.

How many plants do you have? If there are only a few, I would suggest you move them to pots where the soil media can be controlled.

RM

My ph meter is calibrated and double checked for accuracy. No I can't move the plants.