Gentians are a family of plants that include a common plant called Persian violets. They are often grown as house or potted plants, but also grow outdoors. They make excellent additions to rock gardens with lovely small purple, white or blue flowers. Gentian violets are not difficult to remove and since they do not typically survive a transplant, it is best to just throw them out. If you want to grow gentian violets someplace else, start fresh from seed for best results.
Moisten the soil with 2 inches of water the day before you plan to dig up the violets. This will make it easier to remove them.
Dig up the gentian violet with a trowel. Dig around the plant and cut under the root ball, about 4 to 6 inches deep. If you don't get all the roots, that's OK. It most likely will not grow back.
Wear garden gloves and pull up on the plant with your hands. Shake off the soil from the roots and discard the plant. You can also throw it in your compost pile.