I do see the photo and thanks so much. I suspect those yellow leaves are from either too much moisture in the soil which blocks air or they are in a soil that is not acidic enough to allow the roots to absorb nitrogen. Many evergreens such as rhododendrons and azaleas like a more acid soil so that the nitrogen can be released. The middle tree may be green because it drains better due to a drainage hole in the raised bed or because when the raised bed was filled with soil the good stuff went into the middle of the bed and the trees on the end got more fill or cheap soil. (This is just a guess.) The botanical name is Arbutus unedo and the fruit production is affected by summer drought. This is considered a drought resistant tree but last summer we had some dry spells and this may have caused poor fruit production especially if the trees were young and not established. It makes sense that the one in the middle would have the most moisture due to location so the leaves have more green. As for fertilizer these trees are not heavy feeders but do respond to compost added to soil or as a mulch as they respond well to added mycorrhizae in the soil. Keep growing, Marianne Binetti