As a trial I mixed in different amendments &
compost into a pots where I was growing squash and cukes from seeds.
Tried
wood chunks, wood chips, leaves, brown cubic rot, corn
cob slices, & a wood wafer.
The corn cob trial did the best by far, was surprised.
Next year I plan to bury some corn cobs out in the garden next to some vegetable plants and see if it makes a big difference there also.
http://lowcostvegetablegarden.blogspot.com/2012/09/corn-cob-seedling-mix.html 
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