I think Lori is referring to worm castings, the produce from a worm farm.
The reason it would be of benefit in keeping pests away from
plants, is that it is good for
plants. It feeds them just the right amount of nutrient. It's the perfect organic fertilizer. In the case of making a
plant "taste bad" to pests, a good supply of potassium causes
plant cells to strengthen and toughens them up, making them less palatable to pests. That's why a healthy
plant grown in rich, healthy soil doesn't seem to get attacked as much as one which is struggling in poor, unimproved soil.
So i imagine that's an explanation for Lori's hibiscus too, and your herbs. To get the soil in good condition, so the
plant can protect itself. Feed the soil. Water the soil. Protect the soil. Grow soil. Let the
plant grow itself.
