Q.Growing roses
Why do you recommend Epsom salts for growing roses. It is a water soluble form of magnesium and sulfur, both of which are uncommon deficiencies. I could understand the recommendation if there was a documented soil deficiency of either magnesium or sulfur, but you never mention that. I can’t find any evidence that roses require additional magnesium or sulfur, so I don’t understand what your recommended is based on. Thanks.

I did not write the article. You are correct in pointing out this may be garden tradition than science. Here is an article from a soil scientist on magnesium in garden soil, the claims vs. the science. https://s3.wp.wsu.edu/uploads/sites/403/2015/03/epsom-salts.pdf