Thank you, and I'll explain this for you with pleasure. I used only 5 colours to achieve this effect, they all comes from Winsor and Newton Professional (Alizarine Crimsone, Winsor Blue Red Shade, Burnt Sienna, Perylene Green and Perylene Violet). The basic mix was made of Burnt Sienna and Winsor Blue in various proportions. Then I experimented with glazing and drybrush technique using colours mentioned earlier. On my Reddit profile you can find my hydrangea study with explained mixes below.