Healthy soil and sustainable growing

[Greg Bell <gregbell@znet.com>]

i'm planning on growing potatoes in car tires this year.  free containers 
for container gardening!  sort of a white-trash look, but it allows me to 
stack more tires on top and fill with leaf litter and compost as the 
potatoes grow.

basic question - these are average sized car tires... how many seed 
potatoes can i/should i plant in one tire?  spacing recommendations on the 
package are obviously geared towards machine-based growing.

thanks,
~gb