My hydrangeas are just about to bloom. Is it too late to add lime to the soil to make the blooms blue?

What would happen if I added it now? Thanks.

My hydrangeas are just about to bloom. Is it too late to add lime to the soil to make the blooms blue?
You need Epsom salt for deep blue flowers. It's cheap, find it at your local grocery store for around two bucks. I used it last year while my flowers were blooming, and they were the deepest blue ever. love Hydrangea!
Reply:aluminum sulfate and acidic soil makes them blue.... lime will make them turn pink... but it can take a year or more for the change to happen and that's if you consistently add alittle of this and that as you decide, often over the year..... it's much easier to turn a hydra pink if it's in a pot... in the ground it could take a while.... it's all here...





look on the left for 'color change'...





http://www.hydrangeashydrangeas.com/
Reply:Lime won't make them blue, it will make them pink. Lime increases the pH making the soil less acidic. If you want blue flowers you have to make the soil MORE acidic. Garden Sulfer can help a bit, but you really have to add it to the soil before you plant. If you want to turn them blue after the plant is esablished you need to add something else. I forget what it's called but there is stuff you can buy that acidifiys the soil, it actually says right on the bag " Turns Hydrangeas Blue!"


I think it's Ammonium Sulfate or Aluminum Sulfate but I could be wrong.


You can add it anytime, if the flowers have not come out yet, you can still make them blue. If its too late, you will just have to wait until more flowers come out later in the season. It can't hurt to add it now though.