Hydrangeas are commonly known as Christmas flowers in South Africa because they flower this time of the year. This month they are the pride of the garden as they come into full bloom, even with water rationing. There are new varieties which are repeat flowering giving you another flush of flowers in the New Year. Look out for the different colours of the Endless Summer range. To grow the best is easy following our simple tips.
Caring for Hydrangeas is easy. Growing just over a square meter or more they prefer morning sun or dappled shade all day. As long as they get protection from the heat of the day in a moist but well drained soil. If they are in too much shade they tend to get mildew on the leaves and don't flower well.
All Hydrangeas appreciate a little extra effort when they are first brought home. Although most will tolerate some neglect, they do best in a well-prepared garden bed. Dig the hole at least 2 times the size of the original container or bag. Next mix 1 part compost or acid compost to the excavated soil with a handful of Bone Meal to stimulate root strong roots. Add a handful of BioOcean for flowers and to encourage good growth. Insert the plant, mound the soil slightly and mulch with an additional layer of compost as a mulch.
On the traditional varieties the colour of the blooms is influenced by the pH of the soil - blue if acid and pink if alkaline. To influence the colour for blue, use Shake and Grow Blue or add eggshells to the soil. Acid Compost is also a good way to influence acid soil. To influence pink blooms, fertilise with Shake and Grow Pink or add Agricultural lime.
White Hydrangeas stay white. Their colour won’t change with soil ph. There are hybrid varieties on the market these days that don’t change colour but the colour can be intensified by sorting out the soil.
Although hardy and relatively disease free there are a few things that can hamper the performance of your Hydrangeas. Hydrangeas are susceptible to iron chlorosis which is the yellowing of the leaves over time.
In contrast to nitrogen deficiency, which is expressed as general yellowing of old leaves, iron chlorosis is found on new leaves where the green veins are visible on yellow leaves. Iron chlorosis can be corrected by the addition to iron to the soil. The best way to do this is to use Iron Chelate and you should begin seeing results in a couple of weeks. Apply the iron yearly or whenever symptoms reappear.
As a generic non colour influencing food the Starke Ayres Hydrangea food includes iron so your plants get their iron fix right through the year.
In autumn they turn a lovely golden yellow and then you prune them sparingly in the winter as they flower on old wood from the previous summer.