hello lizzie
your acers should look after thereselves .
the tree fern leaves should be left on the plant . you need to protect the crown .i use electric tape as it has some give in it . i tape the leaves up over the crown then rap with some flees and tape again leaving the leaves sticking out the top so it can still photsynthesise excuse my spelling . you never actualy have to cut the leaves of but some people like them tidy looking . i would if you want to take them of next spring .i hope this helped take care bye for now .

I just throw a thick rug over the crown area when it is frosty. The leaves will get tatty and brown but don't cut them back until the new shoots start to curl out in spring. Also - avoid touching the fronds anyway - they hate being touched and will brown easily. But quite often people want to grab them!!!