The Black Kow composted manure that Bob uses is around $7.00 - $9.00 per 50 lb. bag. The worm casings sound like they would cost $25.00 per 50 lb. bag and you're going to need several bags. Bob uses one 50 lb. bag per 30 sq. ft. of garden with the Black Kow. If this is your last year using these baccy patches, the extra expense for the worm casings will only benefit the next owners of the property after this year. I'm just throwing some figures out there so you can better decide for yourself.