I take fleece off the less susceptible stuff as soon as the temperature rises a bit, and replace it in the evening.
Hostas and anemones are my big concern in the ornamental garden.
Fleece needs to be well supported if we get heavy rain or snow, which we certainly will up here, so any fleece is supported on cloche type hoops (home made years ago by husband using galvanised fence wire and a bench vice).
Oddly, fine mesh like enviromesh seems just as good as fleece for frost protection, but doesn't squash the plants as much as it lets rain through, and it is more durable.
Minus 4C last night....