I would sit them in a bucket of water to rehydrate the roots. We are forecast some cold nights over the weekend, so be prepared to move the bucket under cover if need be or chuck some fleece over it.
It is late to be planting bare-root plants, so if you have compost or well rotted manure to incorporate into the planting holes, that would be good. You are going to have to water regularly as well. The plants will be heading into summer with an underdeveloped root system, so keep that in mind. Decent soil that can retain water without getting waterlogged will really help.
Personally I would not worry about fertiliser at this stage. I would concentrate on getting the plants established and wait until I saw some new top growth before feeding.