Opuntia Base Corking vs. Rot: The Pencil Test

Distinguishing Natural Aging from Rot

As Opuntia matures, the lower stem becomes woody (corking)—turns brown, develops bark-like texture, loses green color. This is normal structural support, not disease.

The Pencil Test

Press the eraser end of a pencil into the discolored area:

• Hard, resistant: Corking—healthy.
• Soft, indents easily: Rot—take action.

If It's Rot

1. Cut 4–6 inches above soft tissue.
2. Inspect cut; recut if any discoloration.
3. Callus 2 weeks; root in dry cactus mix.
4. Discard rotted base and soil.

Structural Support for Top-Heavy Plants

Stake main stem, or propagate upper pads to start new, more manageable plants. Opuntia pads root readily when callused and placed on soil.