Every year we use blood, bone meal, and some miracle gro bloom fert every month. last year i read that someone had grown large peppers - the size you get in grocery stores- by adding sulphur. now we bag soil mix, lots of peat. we added a tbsp or 2 per pepper pot (5 gal) and our peppers for the first time grew larger thant he ones in the grocery store. this is especially a problem with poblanos. and we were very happy but not sure why this could happen.