Try to place a small amount of epsons salt at the base of the
rose and scratch it into the soil,I use 1/2 cup for every foot of growth, and, make sure there is air room between the crown of the
rose stalk and the soil, they also like used coffee grounds /tea bags mixed into the soil,, I'm sure tge roots are fine as it's established now,, Pruning back dead brown branches will revive the replinish the green branches giving them better energy. make sure there is plenty air circulation between branches as well, they like to breath freely, thus eliminating fungus and mold, black spot , water early am and don't allow leaves to get wet,
As a rule of thumb I prune mid Feb and Mid July every year,, I don't know what
zone your in,, but t
roses are pretty hardy, next fall place leaves around it to use as mulch and don't remove them untill you know for sure it will stay warm,, and honestly you don't even have to remove them then because they will decompose into compost eventually which is a good thing!..