Possible Clues:

• See how one would adore and leaves like a shamrock
• Fodder plant, common on lawns
• It's lucky if it has four leaves
• You're well-off if you're in it
• Weed or forage plant (which it's good to be in)
• Plant with three-lobed leaves
• A four-leaved one is considered lucky
• Forage plant (that's luxurious to live in?)
• Growth in this Riley's biography
• Cold fan in plant