Does growing your own really save you money?

I found this interesting blog today.  A man and his wife tracked all the time and expense that went into growing their own vegetables.  Of course this is only considering monetary gain and doesn't take into consideration the exercise, peace of mind and just plain fun that are the best benefits.

Here’s our year-to-date garden summary:

Month	Time	Cost	Harvest
January	4.0 hours	$27.30	–
February	2.5 hours	–	–
March	3.5 hours	$130.00	–
April	5.5 hours	$28.51	–
May	5.5 hours	$110.89	–
June	7.0 hours	$0.79	$50.83
July	11.0 hours	$20.94	$123.68
August	8.0 hours	–	$123.94
September	2.0 hours	–	$152.75
October	5.0 hours	–	$155.77
November	6.0 hours	–	–
December	–	–	–
Totals	60.0 hours	$318.43	$606.97

They said that 2009 will be even cheaper since some of the things they bought in '08 can be reused.  So, it looks like it's worth it, especially if you enjoy doing it.