Hydrangeas Are Changing Their Color

Question From: Chatham-Kent, Ontario, Canada
Q: My blue hydrangeas are turning pink. I was told that cider vinegar is a good way to acidify the earth. I have tried the various types of acidifier that I purchased at my nursery center but it doesn't seem to help. Also my pink plants are turning white. Can you give me the recipe for this home made solution?

A: Mona, it is not the acid soil that turns the flowers blue, it's the aluminum in the soil. It gets tied up in alkaline soil and the plant cannot take it up. Your soil may be low in aluminum and if so all the acid in the world will not blue up your hydrangeas. Best to use aluminum sulfate. That said, don't overdo it or you will damage or kill your plants. Follow the directions. A soil test will give you a better picture of what's needed. Read about hydrangeas in Yardener.com. Best And Happy Yardening, Nancy