Under Hydrangea.

Hi Islay, well if your Hydrangea is in a sunny position you can could grow most annuals depending on your like of colours and there are so many to choose from. I tend to plant bulbs in layers around shrubs and then plant Herbaceious Perennials on top with annuals around them so that I have constant growth, interest and colour. So for instance I will plant bulbs of Snowdrops, Blue Bells, Crocus, Harebells, Anemone, Dwarf Iris, etc in layers and then maybe a Phox, Veronica, Solomon's Seal, Lupins, Monarda........there's so much choice As they mature and establish you get an area that will basically run itself, except for annuals of course.