Want to transform your pink hydrangeas into stunning shades of blue? This Hydrangea Colourant is the secret! It's essentially aluminium sulphate, which, when added to the soil, lowers the pH (makes it more acidic) and allows the plant to absorb aluminium, resulting in beautiful blue blooms. This pack gives you two hefty 500g tubs, so you have plenty for multiple applications throughout the growing season. It's super easy to use: just mix the powder with water and apply it to the soil around the base of your hydrangeas (and other acid-loving plants like camellias). It works on plants in garden beds or in pots, both indoors and out. Remember, it only works on hydrangeas that are naturally pink or purple; white varieties won't change color. Give your garden a pop of gorgeous blue with this simple, effective treatment.
