In our clay, we use a fence post auger machine with a 4 inch drill bit
and drill down 3 feet, pack column with organic fertilizer and compost.
Holes can be any distance from each other.
-- =

J. Kolenovsky, A+, Network +, MCP
=F4=BF=F4 - http://www.celestialhabitats.com - commercial
=F4=BF=F4 - http://www.hal-pc.org/~garden/personal.html - personal webpag=
es