After losing my third Pieris japonica in the last 4 years, I’m ready to give up. I thought exposure to wind might be the problem, so I planted the last couple in relatively wind-protected areas, but to no avail. Even though they were all planted in different areas, they all died the same way – turning dry and brown at the top (the lower leaves were still somewhat healthy and green), then the same thing would gradually happen to the lower leaves. Can this plant be grown successfully in this area or should I give up?
Pieris can indeed be successfully grown in our area. As with boxwood, soil and location are the keys. While these plants share the same requirements for planting location, the soil needs of a pieris are much more difficult to properly provide.
Pieris require a much more acidic soil (pH 4.5-6) and they have little tolerance for clay. To be successful, either prepare a raised bed or remove soil and reconstruct the planting area using loose topsoil, sphagnum peat, and pine bark. Once planted, mulch thoroughly with pine bark and most importantly, keep the soil evenly moist, especially during February and March, when most winter damage occurs. Fertilize just like you would any azalea or rhododendron.
Periodically check the pH of the soil (1-2 times per year) and adjust when necessary. Roots fail to develop when the pH rises above the optimal range, at which point decline may begin. Soil tests are very critical when plants are located near foundations or sidewalks where lime may be leached from the masonry, causing the pH to rise.