I have a hydrangea which I am fairly certain is supposed to be blue.

What is the best time of year to apply colourant you can buy in garden
centres (or Miracid) ? Now or in late winter/ spring? I'm guessing it
will got to waste if I use it now.

Cheers.

--

"I go online sometimes, but...everyone's spelling is really bad,
and...it's depressing"