I have planted these Heucheras in 3s and it seems that one or two in each group fade away to one or two tiny leaves. Soil is well drained and limey. Have recently fed the garden with good compost. What else can I do to revive them?
Do not use peat compost when planting, and if you do, mix it with the soil.
If there are vine weevil larvae present, use a bio-control such as Nemasys or a chemical control such as Provado.