From the time I first began buying plants from Pell’s Nursery in Osteen, Florida I was told to “rough up” the roots when the plant was removed from the pot.
I’m talking plastic pots here, which are the way big plants usually come. Often the plant is a bit root bound from growing in a container. In order for the plant to do well when it’s in the ground, the roots need to know they can now grow outwards.
Some plants with thick roots can actually be sliced, or cut to train them to spread. You do this at a few intervals around the root and dirt ball before it’s set into the ground. The Pell family gave me good advice and I always had excellent luck when adding their trees and bushes to my Florida landscape. Their planting suggestion was a good one.

These days little seedlings are often sold in biodegradable, plantable pots, which will disintegrate in the dirt. We are told to plop the whole thing (minus the bottom, says the label) into the ground. Easy-peasy, no muss, no fuss.
I don’t like it. Why would I want a pot in my garden? And what is it really made of? I also believe it inhibits plant growth. “Peel off bottom of pot for optimum root growth” – it says this on the plastic. So imagine if you let the roots around the sides have that optimum growth chance as well!
In short, it’s not necessary. Treat it like a regular pot and remove it.

I always remove the peat pot when I plant something purchased at the store (in my case the Home Depot). I do this because it releases the roots so they can instantly grow into the garden dirt in a natural way. I see no reason to add a pot to the garden soil. It’s just as easy to remove the plastic wrap and the pot.
This type of pot is often used for starting seeds. When I tried this when growing things for my northern garden, the pots began to turn moldy! So they aren’t necessarily a good choice for that either.

By the way, I’ve found that hot pepper plants are one of the easiest types of vegetable to grow.