I bought a bag of Patio Plus last year from HD. The price sounds right for what I paid then. Unfortunately, I did not remember which pot I put it in so I can't speak to the results. I didn't have anything die on me last year so I guess it worked out OK.
I bought some bone meal and will add that to the recipe. And I've got a bag of worm castings for $9. The woman at the garden store said it was a good price because she cut out the middle man. So I guess she got it straight from the worms.