I wish to apply 12-12-12 fertilizer to my rose bushes this year. All of the 12-12-12 fertilizers I have found on the internet are advertised for lawns. Can I apply an all purpose 12-12-12 fertilizer on my roses without harming them? Any info you can provide on fertilizing roses will be appreciated. I have researched the web and many gardening books and they all contradict each other regarding fertilizing roses and it is getting very frustrating! Thank you so much for your help.
To get the best fertilizer for your roses, you need to start with a soil test to see how your soil is currently doing. The Garden Professors blog from 1/13/18 (Facebook.com) mentions that fertilizing without testing can easily lead to toxic high levels of nutrients. When nutrients are way out of balance, it also affects the ability to utilize calcium, for instance. On the whole, you are right that recommendations are all over the map which only indicates that there isn't a one-size-fits-all answer. Some sites recommend rotating whatever food you are using to balance things out. It sounds like a lot of guesswork and not much science are behind commercial products. 20-20-20 sounds mighty strong unless you are using it sparingly.