When receiving the Musa 'Dwarf Cavendish', do not repot immediately but wait at least 3 months or if the roots are beginning to get crowded and growing through the drainage holes. They can grow very fast in their first year. As they get older, you can repot annually.
Repot in the spring, using a 2 inches bigger pot to give the roots room to spread.
Place a piece of screening at the bottom of the container over the drainage hole to secure the soil and allow to drain. Use a rich, well-draining indoor potting mix with perlite for drainage.
Water your plant in the old pot before transferring over and let sit an hour.
Add well-draining potting soil and perlite to the bottom to elevate the root ball. Lift the plant and release the roots against the existing planter. Use a clean knife or garden trowel to wedge between the pot and the soil to loosen.
Inspect the root ball. Notice if there are any dead or rotting roots and trim off with sterile pruners. If the plant is rootbound, cut through the roots to alleviate continued encircling.
Ensure the plant is sitting about 1 inch below the edge of the pot to avoid water spillage. Add more soil and backfill around the sides by tamping down. Fill up to the soil line but not over.
Water thoroughly, and if settling occurs, add more soil.
Water well to dampen the soil and let drain.