Answer: Your soil is probably sandy, which is good for drainage, but you will want to reinforce it with a hefty dose of organic material such as compost (either from your own compost heap or purchased), mushroom compost, composted cow manure, etc. When installing my rose bed I added (amounts will be dependent upon the size of bed you are preparing) a few bags of pre-bagged top soil, a few bags of mushroom compost, a small bag of composted cow manure, and a small bag of sand (of course, you have already covered that portion of the mix). I combined all of these ingredients in a wheel barrow, mixed well, and tilled the mix into the area designated as my rose bed. I add either mushroom compost or composted cow manure to my rose bed every year (usually a 10 lb. bag). I have one rose that I have never applied any other fertilizer to except organic material and it does just as well as the ones I apply fertilizer to.
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