Question

why do insectivorous plants like pitcher plant grow only in the soil which has less nurients.

Answer 1

Carnivorous plants have adapted to grow in places where the soil is thin or poor in nutrients.This method enables the plants to compensate by getting nutrients from insects.

Pitcher plant derives some or most of its nutrients from trapping and consuming animals or protozoans, typically insects and other arthropods. That is why they are known as insectivorous plants or carnivorous plants.