I have two yellow flowered brugmansias which have been in these pots for 3 or 4 years. They needed watering at least twice a day last summer. They’ve been kept in the garage since last autumn, and lightly watered occasionally.

The RHS recommended root pruning.

They came out of their (plastic) pots easily, and I sawed off the fine roots around the edges and the bottom. The soil and roots cut off half filled the pot, which was perhaps a bit more severe than I intended. We’ll see what happens