Topband: K9AY loop -- adding additional radials?

[Peter Bertini]

Hello to the group.  I installed a K9AY system last week and added four 21
foot radials on ground radials with a ground rod at the center.  The
antenna didn't seem to have much directivity, so today I added another four
4-ft inexpensive TV type ground rods at the ends of each of the radials.
We've had some heavy rain, but tonight I am noticing excellent nulls on
European stations when changing directions.  The antenna is located in a
wooded area, and I had assumed the ground was fairly conductive, but
apparently not... would adding another set of four radials in between the
existing four improve the system?  I am not sure how much the change
relates to the heavy rains or adding the grounds.

Pete