A four foot square clump of plump new peony shoots were highlighted at Kew Gardens by the grey, gravel mulch around them. I have not suffered from slugs on Peonies, nor have they had problems with rotting, so I do not put gravel around my plants. However if it is OK for Kew then I guess it is OK for me. At least it would be a decorative improvement on my bare soil.
Ask two gardeners about mulch and you will get three answers. For example when asking about mulching Peonies I got these answers ‘Three popular choices are straw, compost or dry leaves.’ ‘Some popular spring mulches are shredded bark, pine nuggets or straw.’ So no gravel there then!
Planting deeply may prevent the peony from flowering, they do better for a bit of frosting on the crown apparently. Peonies can live for over 50 years and mine flower just fine so I am leaving things as they stand ie. very occasional mulch when the compost heap has generated compost to spare .
