Possible Clues:

• The saffron
• Bulbous plant with brilliant coloured flowers
• 'Spring flower, source of saffron (6)'
• Spring plant
• Long-tubed iris relative
• Dangerous reptile descending on American plant
• Small reptile spotted on American plant
• Large reptile by American's small perennial plant
• Flower in earthenware pot, briefly placed on top of us
• Perennial reptilian superpower