New gooseberry bushes

If by Erica compost you mean ericaceous? No, not really that is for blueberries,rhododendrons & camellia. Best to buy a good quality John innes no.3 if it’s going in & staying in a pot.

If you just want to use it up, that’s fine for planting.  It will break the earth up a bit and it is not that acid anyway. It just doesn’t contain lime that would upset an ericaceous plant.