A number of years ago I purchased some "Tulameen" raspberry plants and planted them in two raised beds. They produced extremely well for many years, but are now producing few healthy new canes. I remember Dr. Hugh Daubeny mentioning that raspberry plants should not be planted where others were previously grown. However, I now wish to replant, but do not have any option other than planting them in the same beds. Is it acceptable to replant in the same beds if I remove the older plants, roots and all the soil and fill the raised beds with new soil?