Answer: Hydrangeas thrive in acid soil. Depending on the species, the soil should have a pH somewhere between 5.0 to 6.5. Our desert soils are alkaline, with a pH between 8 and 8.5.
Although a soil's pH can be modified somewhat on a temporary and localized basis, the difference between 5 and 8 is quite a stretch.
Unfortunately, hydrangeas just don't do well in the demanding conditions of the low desert, even in containers.
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