Related Clues:

• Go off regularly on time, always at the start
• Decay (which can be dry)
• Tomato problem
• Arborist's anathema
• Go green, perhaps?
• Become unsafe to eat
• Rust on surface -- will nothing stop it?
• Tease one another (informal)
• Turn putrid
• Decay, like wood
• Go off tripe
• Go green, maybe?
• Get mushy in the fridge, say
• Go bad, like a jack-o'-lantern two days after carving, seemingly
• Penned unlimited rubbish