The bushes are planted pretty close to each other and they have a tree to deal with. To me it appears quite clearly to be nitrogen starved, in fact all 3 are starved. The reason the other two are not as light could simply be the difference in plant type or more likely it is due to that plant being in the middle so it has competition on both sides for nutrients. A good sign the plants are getting all the energy they need is large dark green leaves and new....I call them bull shoots coming from the base of the plant. You can see one nice size new shoot on the plant on the right but that is it. On young plants you want to see 2 per plant minimum and they should be pencil thick. I would strongly suggest you get some water soluble ammonium SULFATE not ammonium nitrate. Use 1 tsp per gallon of water and do that weekly giving 2 gallons per plant. Make sure the plants are not dry when you give it. The plant should green up pretty fast. The ammonium sulfate is 21-0-0. For those that say what about the other needed elements? Ignore them for now. The BB need the nitrogen constantly but only need the P and K now and then, same goes for all plants. For inground plants that are mulched there is generally enough native P and K anyway. I have not given my 200 or so in ground BB any P or K yet this year just nitrogen weekly since mid February. Potted plants are different and need more P and K added more often. One of the problems with our "soil" is fertilizer tends to wash right through. Ammonium sulfate clings tightly to the soil and resists being washed out. Here is a picture of what you want your leaves to look like. This is on one of my bushes. While those leaves may look big last year Floralcity Lou had leaves on his potted plants that were even bigger. This year I have him beat :) as he was overrun with new projects. Bet that is more than you wanted to know lol.

Wonder if you ever found out the problem with your blueberries. It might be that the location may be too hot. I find that part shade [dappled] to full shade seems to work the best for the blueberries. Blueberry leaves will fry in the full sun here in our desert climate. Make sure that they are planted in very composted and acid type soil. Water several times a week. I also provide overhead spray for humidity.

What you are suggesting I have tried on other single stem plants, but was not successful. If it were possible to split the stem, or trunk down through the roots so each half would have some of the crown AND some roots you might do it, but I don't think it is possible with the plants you have. I also do not think any dressing or sealing material would help. Al

Jshar where I am we have had heat over 100F quite a few days over the last couple of weeks and I noticed some of my blueberry leaves crisped a little. It is not to the same extent as yours, but I wonder if maybe the 2 varieties that crisped are less tolerant of high heat, while the one that is fine is more tolerant? I’m assuming you may have had heat like me though. My two bushes have been here 3 years and are going like gangbusters. They seem to do well in my dry, high heat. They’re “Bountiful Blue” blueberries from Monrovia. I have been eating handfuls of berries from them every morning and there’s still lots more! What type is the one that’s doing well in your yard?