Forgot the photos

Give them time to see where they're at. You really need to wait until fall before doing anything else drastic. They don't turn on a dime when pH is an issue.

I've been growing blueberries for years now, mostly in ground, but some in pots in zone 7b. My favorite is Chandler high bush and Jersey as a low bush pollinator. For the life of me, I don't understand why you would put Blueberry in a fast draining 5-1-1 Citrus mix (I also grow Citrus in pots). You CANNOT OVERWATER a Blueberry is an old saying, and the potting mix should be slow draining if anything and heavy in peat moss. They also like less than all day sun if out in a field or something 4 to 6 hours direct is more than enough. They are understory shrubs by nature. I see chlorosis in the leaves on pics 1 and 2, Miracle grow for acid lovers with a teaspoon of vinegar/gallon. New growth on blueberries is often pale green/red and OK, not to worry as in pic 3. I would not expect them to get better in a 5-1-1 mix.

I have never really paid much attention to the 5-1-1 potting mix until now, since I used store bought acid potting mix for all my blueberry plants which I know Dan doesn't have access to in his area.

A ratio of 5 pinebark to 1 peat and 1 perlite does seem quite drying. Unless you're using composted fine (grounded) pinebarks which are softer and denser than coarse pinebark chips - and retains moisture for a bit longer.

I'm using a ratio of 30% coarse pinebarks with 70% store bought acid potting mix (a combination of 50% composted fine pinebarks + 50% peatmoss + a bit of perlite). I placed half of the coarse pinebark chips at the base of the container for drainage and mixed the other half with the acid potting mix. So far, all my potted blueberry plants are growing very well in it. No signs of yellowing leaves or stress. I water (added vinegar) them every 4 to 5 days in winter (without mulch) and every 3 days in summer (with mulch).

Iron chlorosis only affects new growth so the older leaves should still be green, which it isn't the case here as Dan said - some are turning yellow all over. Maybe it's more than just iron chlorosis.

Since you have just transplanted them, maybe try holding off ammonium sulfate for a month until they've settled in in the new potting mix? You're doing too much too fast. You're fertilising them right after transplanting. Try watering them with diluted white vinegar + water for a week or two. I know we're tempted to see our blueberries growing like fruitnut's plants.

Have you tested your potting mix ph? Some pinebark have neutral ph, not all are under 5.5 ph. You can test the ph level wih a ph testing dye kit. Not sure how much they're in the U.S but they're pretty affordable in Australia https://www.bunnings.com.au/manutec-garden-care-products-soil-ph-test-kit_p3016727

You said the sweetheart variety is doing well in the new potting mix, maybe the soil ph is just right or that it can tolerate and grow in a higher ph medium. You'll never know unless you test the ph. Blueberries are pretty self sulfucienf just as long the ph is between 4.5 -5.5. A lot of the issues can be fixed with the right soil ph. Otherwise they're a pain to deal with, they'll kick and scream (metaphorically speaking) to let you know they're unhappy little campers.

I had some initial problems testing PH. The 3-in-1 was just all over. Then I moved to litmus paper which was more accurate but hard to pin down to a precise number.

Finally I moved to a digital meter. Made sure it was calibrated and I make a slurry with potting mix and distilled water.

My soft tap water is 7.7 ph... no wonder my plants were dying.

I have started using rain water 100 gal acidified with sulfuric acid.

The old mix was 1:1:1 sand, pete, miracle grow potting soil.

Those plants were 3 years old when I bought them. I have had them for 2 years which makes them sad looking 5 year old plants and I am losing a few each year and this year they just look hopeless.

I also had 2 meyer lemon trees in same mix. The soil was always soggy below surface and since the meyers and we're also showing signs of distress I feared root rot on all the plants.

The 5-1-1 had really great feedback so I figured it would be good choice plus it would allow the watering schedule and ability to flush out the media of salts like Fruitnut recommends.

I don't mind watering every other day. Even though I have been doing that the fact is even though the top feels dry it is still holding a lot of moisture below the surface and isn't soggy at all.

That might change when it gets up to 90+ degrees, we will see.

I am pretty new to this and the two years I have had them they were out of their optimal range for ph. Never fertilized. Never given them any epsom salts. Same with meyers.

I just bought some epsom salt. Should I add that to the feeding schedule? If so what dose?

Currently the ph is between 4.9-5.7. the 4.9 plant got an extra watering with the acidified water which was to strong. I guess I will give them time and see if they bounce back.

I also have one in ground which seems healthy but doesn't get alot of flowers. I suspect because it is mostly shaded. It is under a hickory or walnut tree maybe that acidified the soil... idk

Thanks for all the info! I appreciate the help.