Coral Cactus (Euphorbia lactea crest) Brown Patch: Likely Cosmetic

Hard, Dry Spot = Blemish; Soft = Rot

The brown patch on your coral cactus (a grafted Euphorbia) is probably a physical blemish if hard and dry. Ignore it. If soft/mushy, it's rot from poor drainage (pebbles glued on top, no drain hole).

Check the Pot

• Remove glued pebbles if possible (knife under edge).
• Ensure drain hole; if none, repot into a pot with one.
• Water only when soil is dry halfway down.

No treatment needed for dry blemishes. The plant is a succulent—err on the side of dry.