In article
User Bp writes:

One approach is to simply wait and see if the population increases, but the
fact it hasn't changed much in two years bodes ill for that notion. Some sort

What I have often read, and my experience matches it, is that adding
worms is about as helpful as taking your cash and digging it into
the soil.

Unless earthworms are completely absent (not your case), the
population tends to vary with the soil condition and available food.
If your soil is not inviting to the new worms, they will migrate
or die.

I'll repeat the Ruth Stout rallying call -- you need more mulch.
If the worm food is not staying moist (as often happens with thin
mulch layers), the worms won't eat much, and they won't increase.


--
Drew Lawson While they all shake hands
and draw their lines in the sand
and forget about the mess they've made