Posted on June 26, 2006 at 05:10:31:

Question?
I have a hydrengea plant that is 4 yrs old it bloomed blue flowers when we first planted it..It hasn't bloomed since.If i put aluminum sulphate on it would that help?

Answer:
Aluminum sulphate will turn the flower blue from pink but will not make the plant bloom. Sometimes they can be a little stubborn to bloom. Make sure they are well fertilized and that you are not trimming them at the wrong time of year.