Graham points out that 'overwatering can also cause stress to a Christmas cactus and make its leaves turn red. Check that the soil of the plant is well-draining, and water when the top inch or so ...

DESCRIPTION: The Florida semaphore is a tree-like cactus with a distinct trunk and a cluster of spines at the top. The cactus has a dull-gray, fleshy stem with shrubby branches that can grow to a ...