Do you mean something decorative, like bark chippings or coloured gravel? That should be fine.

Depends - on how deep you planted the daffodils, whether they're dwarf ones or taller ones, and how deep the layer of mulch is going to be, but in principle, yes you can add mulch.

Thank you both,The daffs are tall ones and the mulch is bark chippings as decoration,so it appears to be ok to do this.

Can get on with that that now.