Well, here’s the good news: You want to stress healthy green growth and branching the first couple of years, and some experts even "deadhead" all the blooms to prevent fruit setting, to get a sturdier plant in place. Now here’s the "who knows?" (might be bad,might be good) news: Blueberries are really dependent on a seriously acidic soil, like pH of 4.0 to 5.0, which needs to be achieved with serious pre-planting soil prep of the area, and often subsequent adjustment with some agent afterward as well, usually a sulfur compound of some kind. I am attaching a link to a University of Minnesota bulletin about this for more detail, and another from Ohio State. Sawdust, peat moss and other such materials are added in large amounts toprep the soil, which must also be very well-drained (like nearly sandy) but moisture retentive. Blueberries are often put in raised beds to simplify soil prep somewhat. Not sure what you did before planting, by comparison to these recommendations: http://www.extension.umn.edu/distribution/horticulture/DG3463.html http://ohioline.osu.edu/hyg-fact/1000/1422.html If they don’t have that very acid situation, and good drainage, they will not thrive (or fruit well). As for why some leaves go fall-reddish early, usually that’s a sign a some kind f stress, but not dangerous, generally. By August I always have something or other (Amelanchier, or shadbush, for instance, that thinks it’s close to fall and is coloring a bit). This is expecially common in dry spells.