Possible Clues:

• 'O, Sam I'm blooming well in there (6)'
• Champagne and orange juice drink
• I'm so backward in a flower for Mother
• Boozy brunch beverage
• Yellow-flowered tree
• Midmorning drink
• Cocktail named for a plant
• Drink served in a champagne flute
• Graduate gets to grips with institute and the majority briefly from plant
• Brunch standard