Weston's Mark Cox shares how to keep your hydrangeas blue

Whenever you come across an email where the subject line is typed in capitals you know that either someone is in real pain and needs your help or there’s a deal to be had that is just too good to be true...

I NEED HELP. WE ARE SO embarrassed WE CANNOT SEE OUR FRIENDS ANYMORE. GOODBYE CRUEL WORLD.

Darren, Bob’s partner, was fuming over the fact that his beautiful hydrangeas which where blue last year had flowered pink this year.

According to Darren, Bob should have known that the now pink hydrangea that Bob had gifted to him would ruin his perfect blue and white planting scheme and that Bob must have done it on purpose just to embarrass him because he wouldn’t let Bob have a motor bike.

Bob said Darren was so upset with the situation that he had cancelled all of their forthcoming parties at their house rather than face the shame of that ‘pink eyesore’ as he put it.

So I made contact with Bob and Darren and tried to calm the situation to get their lives, and social lives, back on track.

Hydrangea flowers or their colourful bracts (flowers) are very much like the litmus paper that you used back in your old chemistry lessons. Bob understood but Darren was struggling as he skipped chemistry in favour of media studies.

Anyhow, hydrangeas that are planted into acidic soils, that is soils with a pH value of less than 7.0 on the pH scale, will have blue flowers! Soils with a value greater than pH7 will be alkaline, which results in pink flowers.

Darren was beginning to calm down now as he realised that not all was lost with his blue planting scheme. I told the boys that the major key to success was to provide the plant with aluminium. It is this element that will return the flowers to a gorgeous blue. Within soils that have a high pH level aluminium is not readily available, however by applying aluminium sulphate to the soil you will not only supply the plant with the aluminium it needs but you’ll also reduce the pH value of the soil which will make the element more freely available to the plant.

“Bob,” I said, “lay a good layer of mulch around the base of your hydrangea, mixed with acidic peat each spring. Team this with a dressing of sulphur and aluminium sulphate and where possible use rainwater to water it into the soil. By following that routine your hydrangea will produce beautiful blue blooms year after year.”

You could almost feel the weight of the world being lifted off Bob’s shoulders.

Darren, thrilled to get his blue hydrangea back, then invited me around to meet their friends at their next garden party, so as far as I am concerned job jobbed.

Happiness and harmony, that’s what counts in life – or a Suzuki GSX-S1000F if you’re Bob!