To prevent the weeds from growing back, I highly recommend the mulching technique. Simply apply 2-3 inch thick layer of mulch around the base of your rose plants.
Mulch improves moisture retention for your roses and increase nutrient levels in the soil. Bark, wood chips, compost, and sawdust all make perfect mulches for rose plants.
Mix 1 quart vinegar and a ¼ cup of salt. Vinegar and weeds have always been enemies but for the best results, you should use vinegar with over 20% ethanoic acid.