Cacti are grown by ............cutting.

Answer

**Step-by-Step Solution:**

1. **Understanding Cacti Propagation**: Cacti can be propagated using a method called cutting. This involves taking a part of the plant and allowing it to grow into a new plant.

2. **Identifying the Type of Cutting**: The specific type of cutting used for propagating cacti is known as "stem cutting." This is because cacti primarily grow from their stems.

3. **Process of Stem Cutting**: To propagate cacti through stem cutting, a section of the stem from the parent cactus is cut off. This section is referred to as the "scion."

4. **Planting the Scion**: The cut end of the scion is then planted in the soil. It is important that the cut surface is allowed to callous over before planting to prevent rot.

5. **Growth of New Plant**: Once the scion is planted in the soil, it will develop roots and eventually grow into a new cactus plant. This method allows the new plant to inherit desirable traits from the parent plant.

6. **Conclusion**: Therefore, cacti are grown by "stem cutting."

**Final Answer**: Cacti are grown by **stem cutting**.

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