I like to use a good organic based rose food as it feeds the rosebush and also helps build the soils for a good root zone home for them. Here in Colorado, I get a rose food called Gro-Rich Rose and Perennial Food, made by the Richlawn folks. Also we have a locally made organic rose food called Mile Hi Rose Food that is very good. Here are a couple articles for you to check out too:
https://www.gardeningknowhow.com/ornamental/flowers/roses/prepare-new-rose-beds.htm
https://www.gardeningknowhow.com/ornamental/flowers/roses/best-rose-fertilizer.htm
https://www.gardeningknowhow.com/ornamental/flowers/roses/rose-fertilizer.htm
Do a search at the same website where the articles are for rose care and several links to very good articles will come up for you. Enjoy!!
