If your Christmas or Thanksgiving cactus gets very big and pot-bound, you can divide it. Cut through its thick roots with a sharp, clean knife. You can divide it into two to four pieces, depending on the size of the plant. Replant the divisions in a well-drained cactus potting mix. These new plants may look a bit lopsided, but wait to prune or shape them until after they bloom. That way you’ll avoid cutting off any flower buds.
Helpful Products:
Christmas Cactus Potting Soil
Bloom Booster Fertilizer
Watering Can

If you don’t want to divide your Christmas, Thanksgiving or Easter cactus, you can start a new one from cuttings. Here's how to do it:
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