Persicaria plants in terracotta pot (Braintree CM7)

Moving means I have Persicaria plants to give to a good home, planted in a large terracotta pot for a few years as I wasn’t sure if it would spread. I think it is Persicaria amplexicaulis (Red Bistort / 'Firetail' / 'Dark Red') which are said
”to form dense, clumping mounds. While they will expand in width over time to create a larger clump, they are not aggressively invasive and stay contained to their immediate area. They can be easily lifted and divided every few years.”
It certainly seems to have followed that description within the pot, but you can experiment and see what happens if you liberate them! Flowers late summer into autumn- needs to be kept damp.
Heavy pot - needs collecting from Cressing Road Braintree. Please say when you can collect.