Blue, pink, green or white, these hard to miss voluptuous flower heads captivate us throughout summer. We enjoy them as gifts during our Summer Christmases, and we enjoy them us cut flowers (which dry beautifully too) and then there’s this place, where they just grow in abundance, The Pool Room at Oak Valley Wines.


The most common and popular species of Christmas Roses which are grown in South African gardens are Hydrangea macrophylla, it occurs in two forms – the mophead hydrangea and the lacecap hydrangea. Mopheads form large pom-pom shaped balls of flowers, while lacecap hydrangeas are round and flat with tiny flowers in the centre, surrounded by showy flowers on the outside.


I remember having a conversation with my sister while sipping on an ice cold glass of Viognier looking over a beautiful pink bed of Hydrangeas: what type of soil makes them pink and what type makes them blue. We tried to reason it out logically by remembering it had to do with the pH level. But without a crucial piece of info: which type of soil are we on now? This question couldn’t be answered right there and then. So I decided to make a point of taking note of Hydrangea colours in the various places I see them. The power of deduction and a bit of Googling!

It turns out, while my garden at home, consisting of mostly lime soils, with a high pH will produce pink Hydrangeas but the soils here at The Oak Valley, just 35 km away, produce blue Hydrangeas. Why? Because it consists of ancient sandstone with coarse pieces of silica quartz and shales with low calcium content and a low pH.


Mishka thinks this is pretty cool! You can decide which colour you prefer and add whatever is missing from your soils to decrease of increase the pH.

But first you need to know the pH of your soil and this can easily be tested! Simply dilute one part battery acid with nine parts water and then add some soil. The acid reacts with the shell fragments to release the gas carbon dioxide, so, if the water fizzes it is calcareous, i.e. alkaline. Of course the water used to hydrate your soils may also have an effect, so you can test this by using ‘n pool kit.


This brings me to the value of gardening as a way to teach and bond with your kids. I remember watching my mom as a kid while she watered our beautiful paradise. She was calm, in deep thought and enjoying every little section of her garden, it must have taken her two hours to make her rounds, but this made such an impression on me, I couldn’t help wanting to walk out to her. I wanted to see what she sees, those precious moments, experiencing the results of her green fingers and insatiable passion for gardening. If she didn’t enjoy it that much, perhaps I wouldn’t have been interested.

Slowing down, taking time to switch off the irrigation timer and actually spend real time in that garden you spend so much money on will open a world of curiosity to your kids. It forces us to look closer into nature and try to understand the underlying processes that make up our little backyard ecosystem. Slowing down means we have time to share this knowledge with our children, maybe even sit down and plant a shrub or two with them.


I really believe that it all starts right there, in your backyard, on your balcony, on the windowsill. Just take the time, slow down and enjoy the process.

Then you will know the answer to your sister’s question, because you care enough to know the differences and even give her some tips such as these:

Acidic soil (pH of less than 5.5) will produce blue flowers, while alkaline soil (pH of higher than 5.5) produces pink blooms. You cannot change the colour of white hydrangeas.

  • For blue hydrangeas : Make soil more acidic by adding acidic peat to the soil. Feed plants with 25g of aliminium sulphate dissolved in 5 litres of water at two-weekly intervals from early spring onwards. Feed with Shake n Grow Blue Hydrangea Plant Food.
  • For pink hydrangeas : Make soil more alkaline by adding agricultural lime to the soil. Dust lime at the roots of the plant and water in well at two-weekly intervals from early spring onwards. Feed with Shake n Grow PinkPink Hydrangea Plant Food.

This brings me back to The Oak Valley, where we spent a beautiful afternoon among the Christmas Roses, a place worth visiting!



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