Hydrangeas need iron to maintain a rich blue colour, and when planted in regular soil they never hold that colour that you love. Vitax Hydrangea Colourant, best used in conjunction with ericaceous compost, can help.
Vitax Hydrangea Colourant 250g Hydrangeas are naturally pink, but where the soil contains iron or aluminium salts they will produce blue flowers . If you want blue flowers and your soil isn’t rich in the necessary salts, Vitax Hydrangea Colourant provides the solution. Pale pink varieties tend to blue best, with the darker pink varieties tending to produce mauve/blue flowers. To apply mix the colourant with the soil when planting pot or outdoor hydrangeas or dissolve in water and apply.
