1579 Fanshawe park Road east, London - (519) 455-8873

Weekly Gardening Guide: Keeping them BLUE!

May 10, 2016



Keeping them BLUE!

It is a common misconception that all varieties of hydrangeas depend on the soil’s acidity to change colour, BUT only the flowers of the bigleaf hydrangea (Hydrangea macrophylla) can be changed using soil amendments such as aluminum sulfate. Aluminum sulphate works to safely lower the soil pH - ie make it more acidic - allowing the blooms to turn blue.

When to apply Aluminum Sulphate:
- Apply once in early in spring, when you see flower buds, but before buds break
- Apply again, in late summer if your cultivar is a repeat bloomer.

How to apply:
- Water your plants very well before adding Aluminum Sulphate
- Mix Aluminum Sulphate as directed on the box
- Apply your mixture to the soil at the base of the bush.


Come and get your aluminum sulphate today.


← Back to Blog