Haworthias are relatively easy to root with proper care especially during the early stage. A mild weather over the next ~3 weeks after rooting is essential. A too high or too low temperature reduces plant activities. This not only slows down rooting but also lowers the resistance to pathogen infections which may cause rot.
Moisture in the root zone is the main trigger of rooting. On the other hand, excess water also increases the chance of rotting. Therefore for rooting mediums, moisture retentive components like vermiculite are excellent choices because they need less frequent water supplies.
The plant should be kept in a cool and shaded place during the whole rooting process. This helps the plant establish roots faster because a strong sunlight moves auxins to the top part of a plant and slows down rooting. Don’t water for the next ~1 week. After that when watering, only supply a small amount from the side of the container, or dip the bottom of the container in water shortly. Rewater only when the medium is approaching dryness. In every 2~3 weeks, take the plant out and check if it puts down some new roots. If it does, remove the rooting medium and transfer the plant to the growing medium. Again, don’t water for the next ~1 week. After that, gradually increase the water supply and the light intensity.