What People Say. 1  David Bush and Jim Parsons Authors, Fair Park Deco Fair Park is one of the finest collections of Deco architecture in the country, but it is so much more: the embodiment of Texan swagger, it is a testament to the Texanic task of creating a dazzling spectacle in the darkest days of the Depression..
Hydrangeas turn blue as a reaction to aluminum in the soil. The soil pH should be slightly acidic (5.2 - 5.5). Do a soil test first, to determine your starting pH. Adding aluminum sulfate to the soil will help lower its pH, if necessary. A word of caution: not all plants can tolerate acidic soil and neighboring plants may be adversely affected.
Quick Answer. Black spots on the leaves of hydrangeas are usually caused by a fungal infection named Cercospora hydrangeae. While these blackened spots are mainly an aesthetic issue, the fungus can reduce vigor in the affected hydrangeas and cause premature leaf drop. Continue Reading.