A pic. would help. Scotts premium will work great. It is buffered so ph stays around 6.8. But after some time it loses it buffered ph. Also no need to feed much in that soil. It has nutes already.I used it for years before going to another product. It will work if you take it easy with nutes. Its hard to say witout pic or more info. I think folar feeding can burn plants aswell.