Hydrangea macrophylla are naturally pink bloomers, but can be blue bloomers if the aluminium content in the soil is increased and the acidity is below 6. Alkaline soils above 7 produce pink flowers. So, it’s possible to make your pink-flowering hydrangeas turn blue by changing the composition of the soil using products like Acid Loving Plant Food. This product is a balanced blend of acidifying agents and trace elements that will adjust the pH level of the soil to a range of between 5 and 6, and therefore enhance the blue colour of the hydrangea blooms. It also has the added benefit of preventing and curing Iron deficiencies often found in acidic soils.
Hydrangeas all need feeding every 2 – 3 weeks, especially in the growing season. A specially formulated fertiliser like Hydrangea Food is what they need to keep healthy and growing well. This balanced fertiliser will promote healthy root, plant and flower development in hydrangeas, azaleas, camellias and gardenias.
These products are available at garden centres countrywide. For more information visit www.starkeayres.com
This information was supplied by Lonehill Media, publishers of The Gardener and Die Tuinier magazines. For more gardening tips and advice, visit www.thegardener.co.za