Perched Water Table

J.E. Shields
Wed, 04 Dec 2013 08:45:22 PST
The problem is capillary action holding water in the fine spaces in 
the medium.  Until the hydrostatic pressure of the vertical column of 
water exceeds the capillary attraction/surface tension of the water 
at the bottom of the medium, the water won't flow down and out.

You will always get a better draining bed when the medium is uniform 
from top to bottom.   In addition, the taller the water column, the 
better the top of the bed will be drained.  It's physical chemistry 
or physics at its finest.

Jim Shields

At 08:40 AM 12/4/2013, you wrote:
>Agreed that if the thought is that crocking results in better drainage -
>well, that's a crock of animal fertilizer.
>Bulb in 6 inch wide container, with 1/3 of 12 inch height filled with
>soda cans / packing chips (ghost farts, my brother calls them) /
>whatever should still drain satisfactorily, wouldn't it?.
>Judy in New Jersey ...

Jim Shields             USDA Zone 5
P.O. Box 92              WWW:
Westfield, Indiana 46074, USA
Lat. 40° 02.8' N, Long. 086° 06.6' W

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