On 3 Oct 2003 08:16:58 -0700, (simy1) wrote:

(Scott) wrote in message . com...
Can anyone recommend a source where I could find out how deep various
plant roots need to be to survive? This would be nice to know when
preparing a new garden bed - obviously a carrot needs a deeper bed
than a radish or lettuce, for example.

It depends. Do you want them to survive or to thrive? Tomatoes go down
four feet. Chicory or beet go down six feet.

!!!! I am always surprised at how *shallow* veg plant roots are. Even
in thoroughly tilled and amended soil, when I pull up tomato plants at
the end of the season, the roots (the ones that come up with the
plant) don't seem to be more than 8-10" deep. Of course root hairs may
be deeper, but waaay short of 4'. A beet root tapers to the size of a
toothpick within 6". I can't imagine that 6' of good loose soil is
required to grow one.

Some veg are nourished not by providing great depth, but mounding soil
or compost around a relatively shallow planting -- potatoes, celery.
The directions that came with my asparagus crowns said to trench to a
depth of 18", build a long 5-6" mound in the middle to support the
crowns, and gradually add compost each year.

I also have successfully grown many (small tomatoes, chiles) veg in
pots that were no deeper than 10". Nobody in their right mind (flame
shield on) is going to till and amend a to a depth of 4-6'.